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BACKGROUND/PURPOSE To describe the association between autosomal dominant Best disease and peripapillary angioid streak-like changes. METHODS Case report of two siblings. RESULTS A 76-year-old Caucasian male was referred for evaluation of bilateral macular changes and worsening visual distortion over the preceding 2 years. Best corrected visual acuity (BCVA) measured 20/30 in the right eye and 20/80 in the left eye. Funduscopic examination revealed multifocal yellow lesions in the posterior pole that were hyper-autofluorescent on short-wavelength excitation and corresponded with subretinal hyperreflective material on optical coherence tomography. The posterior pole examination was interesting due to the juxtapapillary involvement of the vitelliform lesions as well as the presence of bilateral peripapillary angioid streak-like changes despite no history of conditions associated with angioid streaks. On further workup, an electro-oculogram revealed reduced Arden ratios and a known heterozygous missense mutation in BEST1 (c.903T>G; p.D301E) was found. The patient's 69-year-old younger brother was brought in and found to have a remarkably similar phenotype, including the presence of angioid streak-like changes associated with the same BEST1 mutation. CONCLUSIONS These two cases demonstrate the possibility of late-onset multifocal vitelliform disease due to dominantly inherited BEST1. A consistent phenotype in this family with macular lesions extending into the peripapillary region, associated with angioid streak-like changes, suggests susceptibility of this region to changes in dominant BEST1-vitelliform macular dystrophy.

A 31-year-old Caucasian woman underwent a standard workup as a potential kidney transplant donor. Kidney donor protocol CT showed a left para-aortic hypervascular mass suspicious for a paraganglioma. Biochemical workup revealed elevated urinary catecholamines, supporting this suspicion. The patient underwent surgical resection with histopathological evaluation that confirmed the diagnosis. Endocrine evaluation 2 years later revealed a family history of a cousin with a history of pheochromocytoma as a teenager. A genetic panel identified a missense mutation in succinate dehydrogenase C (c.202T>C; p.Ser68Pro), which was described as a variant of unknown significance. In silico analysis suggested that it may be a deleterious mutation. We concluded that this mutation may be pathogenic, considering these supporting pieces of evidence and her early-onset paraganglioma. This report highlights the importance of genetic screening in patients with paragangliomas/pheochromocytomas, since many cases are familial. Additionally, it underscores the importance of evaluating and documenting cases of variants of unknown significance.

BackgroundTraditional genotype-phenotype correlations for the succinate dehydrogenase-complex II (SDH) genes linkSDHBvariants to thoracic-abdominal pheochromocytoma-paraganglioma (PPGL) andSDHDvariants to head and neck paraganglioma (HNPGL). However, in a recent study we found strong and specific genotype-phenotype associations forSDHDvariants. In the present study we zoom in on the genotype-phenotype associations ofSDHBgene variants, considering the impact of individual gene variants on disease risk and risk of malignancy.MethodsWe analysed two large independent data sets, including a total of 448 patients with PPGL and HNPGL, and studied the association of missense or truncatingSDHBvariants with tumour incidence, age of onset and malignancy risk using binomial testing and Kaplan-Meier analysis.ResultsCompared with missense variants, truncatingSDHBvariants were significantly and consistently more common in patients with PPGL, by a 20 percentage point margin. Malignancy was also significantly more common in truncating versus missense variant carriers. No overall differences in age of PPGL onset were noted between carriers of the two variant types, although some individual variants may differ in certain cases. Missense variants were marginally over-represented among patients with HNPGL, but the difference was not statistically significant.ConclusionSDHBtruncating variants convey an elevated risk for development of both PPGL and malignancy compared with missense variants. These results further support earlier robust associations between truncating variants and PPGL, and also suggest that the two variant types differ in their impact on complex II function, with PPGL/HNPGL tissues displaying differing sensitivities to changes in complex II function.

The genetic cause of 46, XY Disorder of Sex Development(DSD) still cannot be determined in about half of the cases. GATA-4 haploinsufficiency is one of the rare causes of DSD in genetic males (46, XY). Twenty-two cases with 46, XY DSD due to GATA-4 haploinsufficiency (nine missense variant, two copy number variation) have been reported in the literature. In these cases, the phenotype may range from a mild undervirilization to complete female external genitalia. The haploinsufficiency may be caused by a sequence variant or copy number variation (8p23 deletion). The study aimed to present two unrelated patients with DSD due to GATA-4 variants and to review the phenotypic and genotypic characteristics of DSD cases related to GATA-4 deficiency.

We report detailed functional analyses and genotype-phenotype correlations in 392 individuals carrying disease-causing variants in SCN8A, encoding the voltage-gated Na+ channel Nav1.6, with the aim of describing clinical phenotypes related to functional effects. Six different clinical subgroups were identified: Group 1, benign familial infantile epilepsy (n = 15, normal cognition, treatable seizures); Group 2, intermediate epilepsy (n = 33, mild intellectual disability, partially pharmaco-responsive); Group 3, developmental and epileptic encephalopathy (n = 177, severe intellectual disability, majority pharmaco-resistant); Group 4, generalized epilepsy (n = 20, mild to moderate intellectual disability, frequently with absence seizures); Group 5, unclassifiable epilepsy (n = 127); and Group 6, neurodevelopmental disorder without epilepsy (n = 20, mild to moderate intellectual disability). Those in Groups 1–3 presented with focal or multifocal seizures (median age of onset: 4 months) and focal epileptiform discharges, whereas the onset of seizures in patients with generalized epilepsy was later (median: 42 months) with generalized epileptiform discharges. We performed functional studies expressing missense variants in ND7/23 neuroblastoma cells and primary neuronal cultures using recombinant tetrodotoxin-insensitive human Nav1.6 channels and whole-cell patch-clamping. Two variants causing developmental and epileptic encephalopathy showed a strong gain-of-function (hyperpolarizing shift of steady-state activation, strongly increased neuronal firing rate) and one variant causing benign familial infantile epilepsy or intermediate epilepsy showed a mild gain-of-function (defective fast inactivation, less increased firing). In contrast, all three variants causing generalized epilepsy induced a loss-of-function (reduced current amplitudes, depolarizing shift of steady-state activation, reduced neuronal firing). Functional effects were known for 170 individuals. All 136 individuals carrying a functionally tested gain-of-function variant had either focal (n = 97, Groups 1–3) or unclassifiable (n = 39) epilepsy, whereas 34 individuals with a loss-of-function variant had either generalized (n = 14), no (n = 11) or unclassifiable (n = 6) epilepsy; only three had developmental and epileptic encephalopathy. Computational modelling in the gain-of-function group revealed a significant correlation between the severity of the electrophysiological and clinical phenotypes. Gain-of-function variant carriers responded significantly better to sodium channel blockers than to other anti-seizure medications, and the same applied for all individuals in Groups 1–3. In conclusion, our data reveal clear genotype-phenotype correlations between age at seizure onset, type of epilepsy and gain- or loss-of-function effects of SCN8A variants. Generalized epilepsy with absence seizures is the main epilepsy phenotype of loss-of-function variant carriers and the extent of the electrophysiological dysfunction of the gain-of-function variants is a main determinant of the severity of the clinical phenotype in focal epilepsies. Our pharmacological data indicate that sodium channel blockers present a treatment option in SCN8A-related focal epilepsy with onset in the first year of life.

We present a case report about a Moroccan 3-year-old girl, with an intermediate phenotype of muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A, 8 form. We performed clinical and instrumental evaluation, muscle biopsy, genetic screening of 59 genes for different cerebral malformations, follow-up and review of literature. After investigations, we identified an intermediate new phenotype between the severe and mild form, characterised by significant malformations of the cortex with myopatic symptoms, this increases the genotype–phenotype correlation knowledge about POMGNT2 gene mutations. New homozygous missense mutation on POMGNT2 (c.511 G>A, p.Asp171Asn, rs768063378) was detected.

Congenital cataract can be caused by several systemic diseases and differential diagnosis should be done between infections, genetic or metabolic diseases. We present a case of a 12-month-old girl with bilateral nuclear cataracts that was referred for investigation. Since she did not present a family history of congenital cataracts or metabolic diseases, and her physical examination was normal, a systemic evaluation was performed. Biochemical studies disclosed abnormal galactose metabolism signs. The diagnosis of galactokinase (GALK1) deficiency was considered and the study of the GALK1 gene allowed identifying a pathogenic genetic variant and a predictably pathogenic missense mutation, previously not described. Dietary measures were imposed with a good evolution.

Aims Familial hypercholesterolemia (FH) is currently a worldwide health issue. Understanding the characteristics of patients is important for proper diagnosis and treatment. This study aimed to analyze the phenotypic and genetic features, including threshold cholesterol levels, of Korean patients with FH. Methods A total of 296 patients enrolled in the Korean FH registry were included, according to the following criteria: low-density lipoprotein-cholesterol (LDL-C) ＞190 mg/dL with tendon xanthoma or family history compatible with FH, or LDL-C ＞225 mg/dL. DNA sequences of three FH-associated genes were obtained using whole-exome or target exome sequencing. Threshold cholesterol levels for differentiating patients with FH/pathogenic variant (PV) carriers and predictors of PVs were identified. Results Of the 296 patients, 104 had PVs and showed more obvious clinical findings, including higher cholesterol levels. PV rates ranged from 30% to 64% when patients were categorized by possible or definite type according to the Simon Broome criteria. Frequent PV types included missense variants and copy number variations (CNVs), while the most frequent location of PVs was p.P685L in LDLR. The threshold LDL-C levels for patient differentiation and PV prediction were 177 and 225 mg/dL, respectively. Younger age, tendon xanthoma, and higher LDL-C levels were identified as independent predictors of PVs, while traditional cardiovascular risk factors were predictors of coronary artery disease. Conclusions Korean patients with FH had variable PV rates depending on diagnostic criteria and distinctive PV locations. The reported threshold LDL-C levels pave the way for efficient patient care in this population.

Blau syndrome (BS) is a monogenic autoinflammatory disease caused by mutations in nucleotidebinding oligomerization domain containing 2 (NOD2). BS is characterized by the clinical triad of granulomatous dermatitis, arthritis and recurrent uveitis. Due to the low incidence of BS and the lack of treatment studies with large samples, a specific treatment scheme has not been established. We report the case of a patient with BS that was uncontrollable with various immunosuppressive therapies but had a good response to thalidomide. She had the typical triad of rash, arthritis and uveitis. Gene sequencing indicated a NOD2 heterozygous missense variant (c.1759C > T, p.R587C), which has been reported as a pathogenic mutation. The BS diagnosis was confirmed. After treatment with methotrexate, an anti-tumour necrosis factor (TNF)-α inhibitor and corticosteroids, the patient's clinical symptoms and inflammatory indicators remained uncontrolled, and she experienced multiple side effects, such as hypertension and growth retardation attributed to prolonged corticosteroid use. After treatment with thalidomide, her condition was controlled without recurrence or side effects, and corticosteroids were stopped as soon as possible. This report suggests that thalidomide may be effective for BS treatment, but more research is needed to evaluate its long-term efficacy and side effects.

A 51-year-old woman was admitted because of hypercalcemia. Neck ultrasonography and computed tomography revealed the presence of parathyroid cysts on both sides. After primary hyperparathyroidism was diagnosed by technetium-99m-methoxyisobutylisonitrile scintigraphy, the patient was successfully treated with total parathyroidectomy and autotransplantation. She also had a non-functioning pancreatic neuroendocrine tumor, prolactinoma, and adrenal tumors with subclinical Cushing's syndrome. Given these clinical features and her family history, multiple endocrine neoplasia type 1 (MEN1) was suspected, and germline DNA sequencing revealed a missense mutation (c.1013TC, [corrected] p.Leu338Pro) in exon 7 of MEN1. This case demonstrates the phenotypic and genetic diversity of MEN1.

The purpose of this study was to evaluate the clinical and genetic findings of 53-year-old monozygotic twins who had bilateral otosclerosis and right-sided superior semicircular canal near dehiscence (SSCND). Monozygotic twins at the age of 53 presented with conductive hearing loss and normal tympanic membranes. Detailed audiovestibular testing and computed tomography scan revealed that both patients had concurrent otosclerosis and SSCND. Conservative management (hearing aids) was the treatment for these patients. Exome sequencing (ES) for the twins and their affected mother identified a heterozygous missense variant in the EYA4 (c.1744G>A; p.Glu582Lys) gene. This is the first case report to present these separate entities identified in monozygotic twins with a heterozygous missense variant in the EYA4 gene. Our ES data may imply a possible causal relationship or association between variants in the EYA4 gene and concurrent otosclerosis and SSCND.

Summary Background The rare inversa subtype of recessive dystrophic epidermolysis bullosa (RDEB-I) is characterized by predominant intertriginous skin blistering and marked mucosal involvement. Specific recessive missense mutations in the collagen VII triple helix are implicated in the disease. To date, otological complications have been reported infrequently in this patient group. Methods We conducted an observational, retrospective, double institution case record review of patients with RDEB-I who presented with otological complications between January 2000 and June 2020. Diagnosis was established on the basis of clinical features, family history and mutation analysis of the COL7A1 gene. Results In total, 11 (44%) of 25 patients with RDEB-I in our database (2 paediatric, 9 adult; mean age 40.9 years, range 8–72 years) experienced otological complications. Of these 11 patients, 10 (90.9%) had recurrent otitis externa, 7 (63.6%) had meatal stenosis and 7 (63.6%) had recurrent blistering of the external auditory canals. All 11 patients reported hearing difficulties, with conductive hearing loss confirmed by audiology testing in 6 (54.5%) of these. Of the 11 patients, 3 (27.3%) went on to have implantable hearing aids [2 bone-anchored hearing aids (BAHA) and 1 middle ear implant (MEI)] fitted with favourable outcome, while a fourth paediatric patient presented with a cholesteatoma that was surgically managed. Discussion We observed a higher prevalence of otological morbidity in RDEB-I than previously reported, and present the first case of cholesteatoma in epidermolysis bullosa (EB). Our data indicate that BAHA and MEI are safe and effective treatment options for hearing loss in EB. Clinicians should be vigilant in screening for ear symptoms in RDEB-I and consider early referral to an Ear, Nose and Throat specialist.

Objective Defects in the human solute carrier family 26 member 4 (SLC26A4) gene are reported to be one of the causes of congenital hypothyroidism (CH). We aimed to identify SLC26A4 mutations in Chinese patients with CH and analyze the function of the mutations. Methods 273 patients with primary CH were screened for 21 CH candidate genes mutations by targeted next-generation sequencing. All the exons and exon-intron boundaries of SLC26A4 were found and analyzed. The function of 6 missense mutation in SLC26A4 were further investigated in vitro. Results Among 273 patients with CH, 7 distinct SLC26A4 heterozygous mutations (p.S49R, p.I363L, p.R409H, p.T485M, p.D661E, p.H723R, c.919-2A>G) were identified in 10 patients (3.66%, 10/273). In vitro experiments showed that mutation p.I363L, p.R409H,p.H723R affect the membrane location and ion transport of SLC26A4, ,while p.S49R did not.Mutation p.T485M and p.D661E only affect the ion transport, but has no effect on the membrane location. Conclusion Our study indicated that the prevalence of SLC26A4 mutations was 3.66% in the Chinese patients with CH. Five mutations (p.I363L, p.R409H, p.T485M, p.D661E and p.H723R) impaired the membrane location or ion transport function of SLC26A4，which revealed important role of the Ile363,Arg409, Thr485, Asp661, His723 residues in function of SLC26A4. Because these mutations are heterozygous mutations, the pathogenesis of these patients cannot be explained, and the pathogenesis of these patients needs further study.

Background Autism is one of the most complex, heterogeneous neurological disorders. It is characterized mainly by abnormal communication, impaired social interaction, and restricted behaviors. Prevalence of autism is not clear in Indian population. Aim The present study hypothesized that Y chromosome plays role in sex bias of autism in Indian autistic population. To investigate our hypothesis, we underwent genetic analysis of neuroligin 4Y [NLGN4Y] gene by sequencing 85 male autistic children after screening large population of 1,870 mentally ill children from North Karnataka region of India. Result Detailed sequencing of the single targeted gene revealed nine variants including, one novel missense mutation and eight synonymous variants; this accounts for 88.9% of synonymous variants. A single novel missense mutation is predicted to be nonpathogenic on the functions of neuroligin4Y protein but it slightly affects the local configuration by altering the original structure of a protein by changing charge and size of amino acid. Conclusion Probably NLGN4Y gene may not be the risk factor for autism in male children in Indian autistic population. Functional analysis was an important limitation of our study. Therefore, detailed functional analysis is necessary to determine the exact role of novel missense mutation of neuroligin 4Y [NLGN4Y] gene especially in the male predominance of autism in Indian autistic population.

Background: Pathogenic/likely pathogenic (P/LP) variants in the KCNQ1-encoded Kv7.1 potassium channel cause type 1 long QT syndrome (LQT1). Despite the revamped 2015 American College of Medical Genetics (ACMG) variant interpretation guidelines, the burden of KCNQ1 variants of uncertain significance (VUS) in patients with LQTS remains ∼30%. Objective: The purpose of this study was to determine whether a phenotype-enhanced (PE) variant classification approach could reduce the VUS burden in LQTS genetic testing. Methods: Retrospective analysis was performed on 79 KCNQ1 missense variants in 356 patients from Mayo Clinic and an independent cohort of 42 variants in 225 patients from Amsterdam University Medical Center (UMC). Each variant was classified initially using the ACMG guidelines and then readjudicated using a PE-ACMG framework that incorporated the LQTS clinical diagnostic Schwartz score plus 4 “LQT1-defining features”: broad-based/slow upstroke T waves, syncope/seizure during exertion, swimming-associated events, and a maladaptive LQT1 treadmill stress test. Results: According to the ACMG guidelines, Mayo Clinic variants were classified as follows: 17 of 79 P variants (22%), 34 of 79 LP variants (43%), and 28 of 79 VUS (35%). Similarly, for Amsterdam UMC, the variant distribution was 9 of 42 P variants (22%), 14 of 42 LP variants (33%), and 19 of 42 variants VUS (45%). After PE-ACMG readjudication, the total VUS burden decreased significantly from 28 (35%) to 13 (16%) (P = .0007) for Mayo Clinic and from 19 (45%) to 12 (29%) (P = .02) for Amsterdam UMC. Conclusion: Phenotype-guided variant adjudication decreased significantly the VUS burden of LQT1 case–derived KCNQ1 missense variants in 2 independent cohorts. This study demonstrates the value of incorporating LQT1-specific phenotype/clinical data to aid in the interpretation of KCNQ1 missense variants identified during genetic testing for LQTS.

Spastic paraplegia (SPG) is a syndrome characterised by lower limb spasticity, occurring alone or in association with other neurological manifestations. Despite of the new molecular technologies, many patients remain yet undiagnosed. The purpose of this study was to describe the clinical presentation and molecular characteristics of a cohort of 27 patients from 18 different families with SPG in the south of Spain. We used a targeted next-generation sequencing (NGS) approach to study a proband from each family. Variants in SPG11 gene were the most common cause of SPG in our area. We made a genetic diagnosis in 52% of cases, identified 3 novel variants and reclassified one uncertain variant in SPG11 gene as pathogenic variant. We identified a patient with two truncanting mutation in SPG11 gene and late onset disease and report another missense mutation outside of motor domain of KIF1A gene in a family with pure SPG. Our study contributes to enhance the scientific knowledge of SPG. It is important to note the large group of cases (48%) that were not genetically diagnosed in our cohort. Therefore NGS approach is an efficient diagnostic tool, but it still large the number of non-diagnosed subjects, suggesting further genetic heterogeneity.

Background The role of PI3K/AKT/mTOR pathway hyperactivation in localized brain overgrowth is evolving. We describe two patients with focal cortical dysplasia (FCD) who demonstrated somatic mutations in TSC1 and TSC2 genes in the dysplastic brain tissue but not peripheral blood. Methods Paired whole-exome sequencing was performed on genomic DNA extracted from blood and excised brain tissue in two children with FCD who underwent excision of dysplastic tissue. Results Patient 1, a 14-year boy, had drug-resistant focal epilepsy with onset at 20 months. His brain MRI showed abnormalities suggestive of FCD in the left superior and middle frontal lobes. Patient 2 presented at the age of 10 years with pharmaco-resistant focal epilepsy (onset at six years). His MRI suggested FCD in the left insular lobe. Both patients underwent surgical excision of FCD, and excised tissues were pathologically confirmed to have type IIb FCD. For patient 1, a missense mutation (c.64C > T; p.Arg22Trp) was detected in the TSC1 gene in DNA of dysplastic brain tissue but not peripheral blood lymphocytes. Similarly, for patient 2, a frameshift mutation (c.4258_4261delCAGT; p.Ser1420GlyfsTer55) in the TSC2 gene was identified in the brain tissue but not blood. Both gene variants are likely pathogenic and cause mTOR pathway activation. Conclusion Our report of TSC1/TSC2 somatic mutations in patients with non-syndromic FCD suggests that localized hyperactivation of the mTOR pathway can cause focal malformations during cortical development and presents pharmacological targets for precision therapy in FCD management.

Dynamin-1-like (DNM1L) is a gene located on chromosome 12p11.21 that encodes for dynamin-related protein (DRP1), a GTPase involved in mitochondrial and peroxisomal fusion, which plays a pivotal role in brain development. The missense variant, p.Arg403Cys, is clinically associated with childhood-onset super-refractory status epilepticus, with either subsequent poor neurological outcome or death (described in 13 patients). We present a 20-year-old girl carrying this mutation with a history of two episodes of super-refractory focal myoclonic status epilepticus which manifested as epilepsia partialis continua (EPC) with a 13-year interval, during which she displayed moderate intellectual disability, social and school reintegration, without complete control of myoclonic manifestations. The first status, which occurred at the age of six, was associated with transient left side thalamic involvement and the second episode with right side transient basal ganglia hyperintensity on MRI. After the second status, a persistent vegetative state with both drug-resistant epilepsia partialis continua and reticular myoclonus endured; the MRI showed progressive brain atrophy. In contrast to previous published cases, this new case of childhood-onset DNM1L encephalopathy demonstrated biphasic clinical progression. The main features of our patient were EPC, super-refractory status epilepticus, and transient and migrating subcortical thalamic hyperintensity on MRI at onset. The unusual clinical course is also noticeable, indicating possible epigenetic and/or protective factors, without underestimating the progressive and genetic basis of this encephalopathy. Precise characterization of seizures and whole-exome sequencing are crucial in order to establish early diagnosis.

Introduction Pitt-Hopkins syndrome (PTHS) is a neurodevelopmental disorder caused by mutations in TCF4. Seizures have been found to vary among patients with PTHS. We report the case of a PTHS patient with a novel missense mutation in the gene TCF4, presenting with two types of early epileptic encephalopathy. Case report The patient was a Japanese boy. His first seizure was reported at 17 days of age, with twitching of the left eyelid and tonic-clonic seizures on either side of his body. An ictal electroencephalogram (EEG) showed epileptic discharges arising independently from both hemispheres, occasionally resembling migrating partial seizures of infancy (MPSI) that migrated from one side to the other. Brain magnetic resonance imaging revealed agenesis of the corpus callosum. His facial characteristics included a distinctive upper lip and thickened helices. His seizures were refractory, and psychomotor development was severely delayed. At the age of 10 months, he developed West syndrome with spasms and hypsarrhythmia. After being prescribed topiramate (TPM), his seizures and EEG abnormalities dramatically improved. Also, psychomotor development progressed. Whole-exome sequencing revealed a novel de novo missense mutation in exon 18 (NM_001083962.2:c.1718A > T, p.(Asn573Ile)), corresponding to the basic region of the basic helix-loop-helix domain, which may be a causative gene for epileptic encephalopathy. Conclusions To our knowledge, this is the first report of a patient with PTHS treated with TPM, who presented with both MPSI as well as West syndrome. This may help provide new insights regarding the phenotypes caused by mutations in TCF4.

Background Autosomal recessive polycystic kidney disease (ARPKD) is caused by mutations in the PKHD1 gene. The clinical spectrum is often more variable than previously considered. We aimed to analyze the clinical features of genetically diagnosed ARPKD in the Japanese population. Methods We conducted a genetic analysis of patients with clinically diagnosed or suspected ARPKD in Japan. Moreover, we performed a minigene assay to elucidate the mechanisms that could affect phenotypes. Results PKHD1 pathogenic variants were identified in 32 patients (0–46 years). Approximately one-third of the patients showed prenatal anomalies, and five patients died within one year after birth. Other manifestations were detected as follows: chronic kidney disease stages 1–2 in 15/26 (57.7%), Caroli disease in 9/32 (28.1%), hepatic fibrosis in 7/32 (21.9%), systemic hypertension in 13/27 (48.1%), and congenital hypothyroidism in 3 patients. There have been reported that truncating mutations in both alleles led to severe phenotypes with perinatal demise. However, one patient without a missense mutation survived the neonatal period. In the minigene assay, c.2713C > T (p.Gln905Ter) and c.6808 + 1G > A expressed a transcript that skipped exon 25 (123 bp) and exon 41 (126 bp), resulting in an in-frame mutation, which might have contributed to the milder phenotype. Missense mutations in cases of neonatal demise did not show splicing abnormalities. Conclusion Clinical manifestations ranged from cases of neonatal demise to those diagnosed in adulthood. The minigene assay results indicate the importance of functional analysis, and call into question the fundamental belief that at least one non-truncating mutation is necessary for perinatal survival.

Next-generation sequencing of oral squamous cell carcinoma (OSCC) has revealed TP53 as the most frequently mutated gene in OSCC mutually exclusive with human papillomavirus infection. Oral epithelial dysplasia (OED) is defined as a precancerous lesion of OSCC by the current World Health Organization (WHO) classification; therefore, it is assumed that TP53 mutations occur in early precancerous conditions such as OED. Here, we conducted an integrated analysis of TP53, including whole coding sequencing of TP53, FISH analysis of the 17p13.1 locus, and immunohistochemical analysis for p53 (p53-IHC), in 40 OED cases. We detected 20 mutations in 16 (40%) OED cases, and four cases, each harbored two mutations. FISH analysis revealed six of 24 cases (25%) had a deletion on 17p13.1, and four cases had concurrent TP53 mutations and 17p13.1 deletion (2-hit). Also, the increased frequency of TP53 mutations in higher degrees of OED implies acquisition of the mutation is a major event toward OSCC. p53-IHC revealed that overall cases could be categorized into four patterns that correlate well with the mutational status of TP53. Especially, two patterns, broad p53 expression type (pattern HI) and p53 null type (pattern LS), strongly correlated with a missense mutation and nonsense mutation, respectively. Furthermore, seven of the 40 cases progressed to SCC, and six of these seven cases presented pattern HI or LS. Therefore, patterns HI and LS have a high risk for malignant transformation if excisional treatment is not performed irrespective of the dysplasia grade. Although the current WHO classification mainly focuses on morphological criteria for the diagnosis of OED, interobserver discrepancy appears in some instances of the OED diagnosis. Our immunohistochemical analysis supports a more accurate pathological diagnosis for OED in cases of low dysplastic changes or of differential diagnosis with non-dysplastic lesions.

Background: Heart failure is a hallmark of severe hypertrophic cardiomyopathy and dilated cardiomyopathy (DCM). Several mutations in the β-MYH7 gene lead to hypertrophic cardiomyopathy. Recently, causative mutations in the β-MYH7 gene have also been detected in DCM from different populations. Methods: Here, we sequenced the β-MYH7 gene in 137 Indian DCM patients and 167 ethnically matched healthy controls to detect the frequency of mutations and their association. Results: Our study revealed 27 variations, of which 7 mutations (8.0%) were detected exclusively in Indian DCM patients for the first time. These included 4 missense mutations—Arg723His, Phe510Leu, His358Leu, and Ser384Tyr (2.9%); a frameshift mutation—Asn676_T-del (1.5%); and 2 splice-site mutations (IVS17+2T) T>G and (IVS19-1G) G>A (3.6%). Remarkably, all 4 missense mutations altered evolutionarily conserved amino acids. All 4 missense mutations were predicted to be pathogenic by 2 bioinformatics tools—polymorphism phenotyping v2 (PolyPhen-2) and sorting intolerant from tolerant (SIFT). In addition, the 4 homology models of β-MYH7—p.Leu358, p.Tyr384, p.Leu510, and p.His723—displayed root-mean-square deviations of ∼2.55 Å, ∼1.24 Å, ∼3.36 Å, and ∼3.86 Å, respectively. Conclusions: In the present study, we detected numerous novel, unique, and rare mutations in the β-MYH7 gene exclusively in Indian DCM patients (8.0%). Here, we demonstrated how each mutant (missense) uniquely disrupts a critical network of non-bonding interactions at the mutation site (molecular level) and may contribute to development of dilated cardiomyopathy (DCM). Therefore, our findings may provide insight into the understanding of the molecular bases of disease and into diagnosis along with promoting novel therapeutic strategies (through personalized medicine). Résumé: Introduction: L’insuffisance cardiaque est une caractéristique de la cardiomyopathie hypertrophique grave et de la cardiomyopathie dilatée (CMD). Plusieurs mutations dans le gène β-MYH7 conduisent à la cardiomyopathie hypertrophique. Récemment, les mutations causales dans le gène β-MYH7 ont également été détectées au sein de différentes populations atteintes de CMD. Méthodes: Ici, nous avons séquencé le gène β-MYH7 de 137 patients indiens atteints de CMD et de 167 témoins sains appariés selon l’origine ethnique pour détecter la fréquence des mutations et leur association. Résultats: L’étude nous a permis de révéler 27 variations, dont sept mutations (8,0 %) étaient exclusivement détectées chez les patients indiens atteints de CMD pour la première fois. Parmi ces mutations, nous avons observé quatre mutations faux-sens—Arg723His, Phe510Leu, His358Leu et Ser384Tyr (2,9 %), une mutation par déphasage—Asn676_T-del (1,5 %) et deux mutations des sites d’épissage (IVS17+2T) T>G et (IVS19-1G) G>A (3,6 %). Étonnamment, les quatre mutations faux-sens changeaient les acides aminés évolutivement conservés. Selon deux outils bioinformatiques—PolyPhen-2 (de l’anglais, polymorphism phenotyping v2) et SIFT (de l’anglais, sorting intolerant from tolerant), les quatre mutations faux-sens devaient être pathogènes. De plus, les quatre modélisations de β-MYH7 par homologie—p.Leu358, p.Tyr384, p.Leu510 et p.His723—affichaient de façon respective des écarts quadratiques moyens de ∼2,55 Å, ∼1,24 Å, ∼3,36 Å et ∼3,86 Å. Conclusions: Dans la présente étude, nous avons détecté de nombreuses nouvelles mutations, uniques et rares, dans le gène β-MYH7, exclusivement chez les patients indiens atteints de CMD (8,0 %). Ici, nous avons démontré comment chaque mutant (faux-sens) perturbe de manière unique un réseau essentiel d’interactions non liantes au site de mutation (moléculaire) et peut contribuer à la survenue de la CMD. Par conséquent, les conclusions de notre étude peuvent donner un aperçu des bases moléculaires de la maladie et du diagnostic tout en favorisant la promotion de nouvelles stratégies thérapeutiques (par la médecine personnalisée).

Oncogenic mutations in the adenomatous polyposis coli (APC)/Wnt signaling pathway are well documented. The FBXW7 gene (F-box and WD repeat domain-containing 7) encodes a member of the ubiquitin-proteasome complex that is more recently described to antagonize the oncogenic Wnt pathway by promoting the degradation of β-catenin encoded by the CTNNB1 gene. The pathologic significance of FBXW7 mutation in colorectal carcinoma (CRC) remains under-reported. In this study, we report the clinicopathologic and β-catenin immunohistochemical features of a single-institution cohort (83 cases) of FBXW7-mutated CRC compared with CTNNB1-mutated CRC. FBXW7-mutated CRC was more common in older patients (p = 0.031) and in the left/distal colon (p = 0.022). Immunohistochemical analysis revealed that aberrant nuclear/cytoplasmic β-catenin localization was identified in a significantly high proportion of FBXW7-mutated CRCs. When compared with CTNNB1-mutated CRC, FBXW7-mutated CRC showed a significantly higher proportion of microsatellite instability-stable tumors with intact expression of DNA mismatch repair proteins and had significantly more frequent co-occurrence of missense TP53 and KRAS mutations. The most frequently mutated FBXW7 residues/hotspots were located within the WD repeat domains (aa 378-659), which were also associated with aberrant nuclear/cytoplasmic localization of β-catenin protein. Our results indicate the unique pathologic characteristics of FBXW7-mutated CRC with frequent co-occurrence of missense mutant TP53 and KRAS. The mutated FBXW7 residues/hotspots and its association with aberrant nuclear/cytoplasmic β-catenin localization further support the oncogenic role of FBXW7 in colon carcinogenesis.

Alkaptonuria (AKU), a rare genetic disorder, is characterized by the accumulation of homogentisic acid (HGA) in the body. Affected individuals lack enough functional levels of an enzyme required to breakdown HGA. Mutations in the HGD gene cause AKU and they are responsible for deficient levels of functional homogentisate 1,2-dioxygenase (HGD), which, in turn, leads to excess levels of HGA. Although HGA is rapidly cleared from the body by the kidneys, in the long term it starts accumulating in various tissues, especially cartilage. Over time (rarely before adulthood), it eventually changes the color of affected tissue to slate blue or black. Here we report a comprehensive mutation analysis of 111 pathogenic and 190 non-pathogenic HGD missense mutations using protein structural information. Using our comprehensive suite of graph-based signature methods, mCSM complemented with sequence-based tools, we studied the functional and molecular consequences of each mutation on protein stability, interaction and evolutionary conservation. The scores generated from the structure and sequence-based tools were used to train a supervised machine learning algorithm with 84% accuracy. The empirical classifier was used to generate the variant phenotype for novel HGD missense mutations. All this information is deployed as a user friendly freely available web server called HGDiscovery (http://biosig.unimelb.edu.au/hgdiscovery/).

Persistent Mullerian duct syndrome (PMDS) is a rare clinically and genetically overlapping disorder caused by mutations in the anti-Mullerian hormone (AMH) gene or the anti-Mullerian hormone receptor type 2 (AMHR2) gene. Affected individuals present uterus and tubes in normally virilized males and are discovered unexpectedly during other surgeries. Since it is rare and complex, a definitive clinical diagnosis can be missed, and there are no guidelines regarding how to deal with the uterus. In the present study, exome sequencing and Sanger verification were performed for causal variants in 12 PMDS patients. Preoperative diagnoses were made by positive exome sequencing in 8 patients. Of them, 7 patients evoked on the basis of ultrasound indicating bilateral testes on the same side of the body. Twelve different AMH variants (2 frameshift/nonsense, 1 deletion, 8 missense, and 1 in-frame) in 9 patients and 6 different AMHR2 variants (5 missense and 1 splicing) in 3 patients were identified. Seven variants were classified as "pathogenic" or "likely pathogenic", and 4 of them were novel. All but two patients with AMH defects showed low serum AMH concentrations, but all patients with AMHR2 defects showed elevated AMH levels. During surgery, an abnormal vas deferens was observed in half of the patients. Eight patients underwent orchidopexy with uterine preservation. Of them, 2 patients presented complications including irreducible cryptorchidism, and 3 patients developed Mullerian remnant cysts. Three patients underwent subtotal hysterectomy. Of them, one patient had complication of injury to the vas deferens, and one had hemorrhage after operation. This is the first report of PMDS involving a large Chinese population. The present study not only expands the variation spectrum but also provides clinical experience about the management of the uterus.

We herein describe a Charcot-Marie-Tooth disease (CMT) family with a MFN2 mutation with atypical ocular manifestations. The proband, his mother, his third daughter, and his deceased maternal grandfather all had symptoms of CMT and a visual impairment (either cataracts or severe astigmatism). On whole-exome sequencing for the proband having CMT and congenital cataracts, we identified a c.314C>T (p.Thr105Met) mutation in MFN2, but no mutation in the causative genes associated with cataracts. This missense mutation in MFN2 co-segregated with CMT and the atypical ocular manifestations in this family. The findings of this study might help to expand the clinical phenotype of heterogeneous MFN2-related CMT.

Aims Mutation type, location, dominant-negative I Ks reduction, and possibly loss of cyclic adenosine monophosphate (cAMP)-dependent I Ks stimulation via protein kinase A (PKA) influence the clinical severity of long QT syndrome type 1 (LQT1). Given the malignancy of KCNQ1-p.A341V, we assessed whether mutations neighbouring p.A341V in the S6 channel segment could also increase arrhythmic risk. Methods and results Clinical and genetic data were obtained from 1316 LQT1 patients [450 families, 166 unique KCNQ1 mutations, including 277 p.A341V-positive subjects, 139 patients with p.A341-neighbouring mutations (91 missense, 48 non-missense), and 900 other LQT1 subjects]. A first cardiac event represented the primary endpoint. S6 segment missense variant characteristics, particularly cAMP stimulation responses, were analysed by cellular electrophysiology. p.A341-neighbouring mutation carriers had a QTc shorter than p.A341V carriers (477 ± 33 vs. 490 ± 44 ms) but longer than the remaining LQT1 patient population (467 ± 41 ms) (P Conclusion KCNQ1 S6 segment mutations surrounding p.A341 increase arrhythmic risk. p.A341V-specific loss of PKA-dependent I Ks enhancement correlates with its phenotypic severity. Cellular studies providing further insights into I Ks-channel regulation and knowledge of structure-function relationships could improve risk stratification. These findings impact on clinical management.

Hypohidrotic ectodermal dysplasia (HED) is a rare genetic disorder caused by mutational inactivation of a developmental pathway responsible for generation of tissues of ectodermal origin. The X-linked form accounts for the majority of HED cases and is caused by Ectodysplasin (EDA) pathogenic variants. We performed a combined analysis of 29 X-linked hypohidrotic ectodermal dysplasia (XLHED) families (including 12 from our previous studies). In addition to the classical triad of symptoms including loss (or reduction) of ectodermal structures, such as hair, teeth, and sweat glands, we detected additional HED-related clinical features including facial dysmorphism and hyperpigmentation in several patients. Interestingly, global developmental delay was identified as an unusual clinical symptom in many patients. More importantly, we identified 22 causal pathogenic variants that included 15 missense, four small in-dels, and one nonsense, splice site, and large deletion each. Interestingly, we detected 12 unique (India-specific) pathogenic variants. Of the 29 XLHED families analyzed, 11 (38%) harbored pathogenic variant localized to the furin cleavage site. A comparison with HGMD revealed significant differences in the frequency of missense pathogenic variants; involvement of specific exons and/or protein domains and transition/transversion ratios. A significantly higher proportion of missense pathogenic variants (33%) localized to the EDA furin cleavage when compared to HGMD (7%), of which p.R155C, p.R156C, and p.R156H were detected in three families each. Therefore, the first comprehensive analysis of XLHED from India has revealed several unique features including unusual clinical symptoms and high frequency of furin cleavage site pathogenic variants.

Cenani-Lenz syndrome (CLS) is a rare autosomal-recessive congenital disorder affecting development of distal limbs. It is characterized mainly by syndactyly and/or oligodactyly, renal anomalies, and characteristic facial features. Mutations in the LRP4 gene, located on human chromosome 11p11.2-q13.1, causes the CLS. The gene LRP4 encodes a low-density lipoprotein receptor-related protein-4, which mediates SOST-dependent inhibition of bone formation and Wnt signaling. In the study, presented here, three families of Pakistani origin, segregating CLS in the autosomal recessive manner were clinically and genetically characterized. In two families (A and B), microsatellite-based homozygosity mapping followed by Sanger sequencing identified a novel homozygous missense variant [NM_002334.3: c.295G>C; p.(Asp99His)] in the LRP4 gene. In the third family C, exome sequencing revealed a second novel homozygous missense variant [NM_002334.3: c.1633C>T; p.(Arg545Trp)] in the same gene. To determine the functional relevance of these variants, we tested their ability to inhibit canonical WNT signaling in a luciferase assay. Wild type LRP4 was able to inhibit LRP6-dependent WNT signaling robustly. The two mutants p.(Asp99His) and p.(Arg545Trp) inhibited WNT signaling less effectively, suggesting they reduced LRP4 function.

PURPOSE: To identify the genetic causes of multiple morphological anomalies of the flagella (MMAF) and oligoasthenoteratozoospermia (OAT). METHODS: Whole-exome sequencing (WES) was performed on the proband to identify pathogenic mutation for infertility. Western blotting and immunofluorescence analysis detected the expression level and localization of adenylate kinase 7 (AK7). RESULTS: We identified a novel homozygous missense mutation (NM_152327: c.1846G > A; p.E616K) in AK7 in two brothers with MMAF and OAT from a consanguineous family by WES. Western blotting and immunofluorescence experiments determined that the expression level of AK7 decreased in the sperm from the proband. The proband and his wife underwent two cycles of intracytoplasmic sperm injection (ICSI) treatment but got unfavorable outcomes. CONCLUSION: This study could provide precise genetic diagnosis for the patient and expand the spectrum of AK7 mutations.

OBJECTIVE To compare clinical, biochemical, tumoural and mutational characteristics of Von Hippel Lindau Syndrome (VHL)-associated pheochromocytoma (PCC) to multiple endocrine neoplasia 2A (MEN2A)-associated pheochromocytoma. DESIGN Retrospective study design in a tertiary health care centre in Northern India. METHODS A total of 47 patients with biochemical and histologically proven pheochromocytoma/paraganglioma (PCC/PGL): 29 associated with VHL and 18 with MEN2A, were divided in two cohorts, respectively. Analysis of their medical records along with a prospective follow-up was done. RESULTS There were more children

Human epidermal growth factor receptor 2 (HER2) amplification or activating mutations are found in 1.6%–4% of non-small cell lung cancer (NSCLC). Pyrotinib has been reported to have better potency in NSCLC patients with HER2 exon 20 insertion (ex20ins) mutations; however, more clinical evidence is urgently needed to guide pyrotinib-based therapy in NSCLC with HER2 amplification or heterogeneous mutations. We retrospectively analyzed advanced NSCLC patients with HER2 amplification or mutations who were treated with pyrotinib-based therapy between September 25, 2018 and October 30, 2020 in our hospital. Molecular dynamics simulation was used to explore the bioactive conformation and binding mechanisms of pan-ErbB tyrosine kinase inhibitors (TKIs) including pyrotinib for different HER2 ex20ins variants. In this study, 79 eligible patients were included with 70 ex20ins variants, 6 missense mutations and 3 primary HER2 amplifications identified. A775_G776insYVMA insertion was the most common observed subtype. The median progression-free survival (mPFS) was 5.8 (95% CI: 4.1–7.4) months. Use of pyrotinib-based therapy in first-/second-line settings showed a significantly better prognosis than that observed in third-line settings or above (mPFS: 9.1 vs. 4.4 months; P = 0.0003). Compared with HER2 amplification and exon 20 non-YVMA insertion variants, patients with HER2 missense mutations had a visible mPFS benefit (12.2 vs. 6.8 vs. 5.2 months). Computational docking simulations revealed that pyrotinib failed to interact with the specific insertion variant P780_Y781insGSP. These results indicated that pyrotinib-based therapy exhibited good anti-tumor activity and acceptable safety profile in HER2-altered advanced NSCLC.

Aims Fabry disease (FD) is an X‐linked genetic disease caused by mutations in the GLA gene that leads to deficient activity of lysosomal enzymes, accumulation of globotriaosylceramide in multi‐organ systems, and variant clinical manifestations. We aimed to detail the clinical and genetic spectrum of FD in Chinese families. Methods and results Five male probands with unexplained left ventricular hypertrophy and their family members were investigated. Genetic screening was available in 11 subjects of the 5 families, 10 of whom proved to be carriers of either GLA gene mutation, including 3 previous reported missense mutations (c.128G > A, c.811G > A, c.950T > C), 1 novel missense mutation (c.37G > C), and 1 novel deletion mutation (c.1241delT). A total of 17 patients were definitely or possibly diagnosed of FD, given their clinical manifestations and hereditary nature of FD. Echocardiography demonstrated normal cardiac structure and function in six female patients. Electrocardiographic pre‐excitation occurred in 80% (4/5) of men and 16.7% (1/6) of women. Six patients (6/14, 42.9%) had chronic kidney disease with decreased renal function and all were male (6/7, 85.7%). Six patients presented with acroparesthesia, hypohidrosis, or both. Three female patients and two male patients experienced sudden death, and one male patient with the mutation (c.128G > A) died of progressive heart failure, between 41 and 66 years of age. Conclusions We reported five unrelated families of FD with different GLA mutations. Clinical manifestations were highly heterogeneous between male and female patients even within the same family. Female patients showed relatively low risks of structural heart disease and renal insufficiency. However, the long‐term outcomes might be adverse in both sexes. Our study underlines the importance of molecular screening of the GLA gene for early identification and clinical decision making in patients with FD.

Background Mutations in TP53 in myeloid neoplasms patients have been associated with poor prognosis. Effective treatments to these patients remain unclear. Patients and Methods In this study, we retrospectively analyzed diagnostic and outcomes of 31 Acute Myeloid leukemia (AML) and 9 Myelodysplastic syndromes (MDS) patients with TP53 mutation at our hospital from September 2015 to October 2020. Results A total of 42 variants (28 unique variants) in the coding region of TP53 gene were identified, and most were missense mutation (34 of 42, 81%). The median overall survival (OS) was 8 months for the AML patients (1-32 months) and 7 months for the MDS patients (3-27 months). There were 35 and 13 patients underwent frontline chemical therapy and Allo-HSCT, respectively. The overall response rate was 45.3% (16/35) for the frontline treatment. There was no significant difference between intensive and low-intensity regimens on either response to the frontline treatment (P = .255) or overall survival (P = .078). Patients, who achieved complete or partial remission at the frontline treatment, presented a higher survival than patients in non–remission, no matter transplant or not. Conclusion This study corroborates that improving the response to the first-line treatment could prolong the survival of myeloid neoplasms patients with TP53 mutation. Allo-HSCT could be a curative option for patients with TP53 mutation, when in complete remission during the first-line treatment.

Background The neuronal ceroid lipofuscinosis (NCL) are a group of autosomal recessive neurodegenerative disorders that are characterized by the accumulation of ceroid lipofuscins. The NCLs are categorized into four classes based on the age of onset. Kufs disease is a rare adult-onset NCL caused by mutations in the CLN6 gene, which is rarely observed in the Japanese population. Case We previously reported a case study on a patient with Kufs disease, whose parents had a consanguineous marriage. Later, we observed another unrelated patient with Kufs. Here we present the case and mutational gene report in patients with Kufs disease. Conclusions Gene analysis results of the first patient revealed a homozygous mutation c231C > G, p.Asn77Lys in exon 3 and a homozygous c.297 + 48 A > T mutation in intron 3 in the CLN6 gene. The Asn amino acid is perfectly conserved among species. In silico analysis showed that the mutation is predicted to be probably damaging. Moreover, the second patient with Kufs disease also had the same homozygous mutations. These data suggest that the missense mutation must be pathogenic. Furthermore, the patients had lived in the same district; therefore, they both potentially inherited the founder effect mutations.

Gap junction beta 1 (GJB1) is the pathogenic gene of X-linked Charcot-Marie-Tooth type 1 (CMTX1), a rare hereditary sensorimotor neuropathy. However, different mutations of GJB1 result in heterogeneous clinical manifestations with only some mutations leading to central nervous system involvement. We previously reported two GJB1 missense mutations: one novel mutation (c.212T > G) found in a CMTX1 family that only manifested as peripheral neuropathy, and another previously reported mutation GJB1(c.311A > C) leading to involvement of the peripheral nerves and cerebral white matter. However, the mechanism by which GJB1 mutations lead to CMTX1 has not been fully characterized. Here, we generated Schwann cells and primary cultured oligodendrocytes with these two mutations, resulting in the Cx32I71S (GJB1 c.212T > G) and Cx32K104T (GJB1 c.311A > C) mutants, to analyze the pathogenic mechanism using cytology, molecular biology, and electrophysiological methods. Both mutants showed abnormal endoplasmic reticulum aggregation, especially the Cx32K104T mutant, leading to an increase in endoplasmic reticulum stress, resulting in apoptosis. Furthermore, whole-cell patch clamp experiments in oligodendrocytes revealed that the Cx32K104T mutant reduced the cell membrane potential and inwardly rectifying potassium currents, which may be a vital element for central involvement. Therefore, our results may provide a new perspective for understanding the pathogenesis of CMTX1.

Aminoacyl-tRNA synthetases (aaRS) are ubiquitously expressed enzymes responsible for ligating amino acids to their cognate tRNA molecules through an aminoacylation reaction. The resulting aminoacyl-tRNA is delivered to ribosome elongation factors to participate in protein synthesis. Seryl-tRNA synthetase (SARS1) is one of the cytosolic aaRSs and catalyzes serine attachment to tRNASer . SARS1 deficiency has already been associated with moderate intellectual disability, ataxia, muscle weakness, and seizure in one family. We describe here a new clinical presentation including developmental delay, central deafness, cardiomyopathy, and metabolic decompensation during fever leading to death, in a consanguineous Turkish family, with biallelic variants (c.638G>T, p.(Arg213Leu)) in SARS1. This missense variant was shown to lead to protein instability, resulting in reduced protein level and enzymatic activity. Our results describe a new clinical entity and expand the clinical and mutational spectrum of SARS1 and aaRS deficiencies.

Purpose Loss of function variants of the transient receptor potential cation channel, subfamily V, member 6 (TRPV6) have been recently associated with chronic pancreatitis (CP) in Japanese, German and French patients. Here, we investigated the association of TRPV6 variants with CP in independent European cohorts of early-onset CP patients from Poland and Germany. Patients and methods We enrolled 152 pediatric CP patients (median age 8.6 yrs.) with no history of alcohol/smoking abuse and 472 controls from Poland as well as 157 nonalcoholic young CP patients (median age 20 yrs.) and 750 controls from Germany. Coding regions of TRPV6 were screened by Sanger and next generation sequencing. Selected, potentially pathogenic TRPV6 variants were expressed in HEK293T cells and TRPV6 activity was analyzed using ratiometric Ca2+ measurements. Results Overall, we identified 10 novel (3 nonsense and 7 missenses) TRPV6 variants in CP patients. TRPV6 nonsense (p.V239SfsX53) and missense variants showing significant decrease in intracellular Ca2+ concentration in HEK293T cells (p.R174X, p.L576R, p.R342Q), were significantly overrepresented in Polish patients as compared to controls (6/152, 3.9% vs. 0/358, 0%; P = 0,0007). Nonsense TRPV6 variants predicted as loss of function (p.V239SfsX53 and p.R624X) were also significantly overrepresented in German patients (3/157; 2.0% vs 0/750; 0%, P = 0.005). Conclusions We showed that TRPV6 loss of function variants are associated with elevated CP risk in early-onset Polish and German patients confirming that TRPV6 is a novel CP susceptibility gene.

Background and aims Porokeratosis (PK) is a heterogeneous group of cutaneous keratinization disorders and has five clinical subtypes. DSAP is the most common clinical subtype and is characterized by multiple small, annular, anhidrotic, keratotic lesions predominantly on sun-exposed areas of the skin. It is an autosomal dominantly inherited epidermal keratinization disorder. However, studies on its molecular basis is limited. Materials and methods We performed mutation analysis of genes in four pedigrees and three sporadic cases of DSAP in the Chinese population. Genomic DNA was extracted from blood samples obtained from patients, unaffected family members, and 100 unrelated individuals. All exons and flanking intron sequences of the mevalonate kinase (MVK) and farnesyl diphosphate synthase (FDPS) genes were amplified. Results One missense mutation in exon 7 (C.G677A) of the MVK gene was identified in pedigree 3, and one missense mutation in exon 5 (C.C535T) of the FDPS gene was identified in sporadic case 3. No mutation was detected in the MVK and FDPS genes in the remaining three pedigrees and two sporadic cases with DSAP. Conclusion Our results may be useful for genetic counseling and prenatal diagnosis of affected families and for expanding the repertoire of MVK and FDPS mutations underlying DSAP.

Objective. Homozygous OCLN variants have been reported in patients with band-like calcification with simplified gyration and polymicrogyria (BLC-PMG) which is characterized by microcephaly, intracranial calcification and severe developmental delay. The OCLN gene encodes the integral membrane protein, occludin. Methods. Herein, we report three additional cases with homozygous OCLN variants that were identified via Trio-WES in two consanguineous unrelated families. Results. We detected a previously reported frameshift variant in two cases in Family 1 and a novel missense variant in a case in Family 2. The potential pathogenicity of both variants in the index cases was investigated using in silico tools, and both variants were determined to be rare and predicted to be pathogenic. All of the presented cases exhibited clinical features in common with earlier reported patients, such as severe intellectual disability, microcepha-ly, polymicrogyria, epilepsy, hypotonia and severe developmental delay. On the other hand, in addition to the common phenotypic features, our two cases in Family 1 showed features similar to those previously reported in cases from two Turkish families carrying the same frameshift variant, such as renal failure. Significance. We herein expand the spectrum of OCLN gene variants with a description of an additional novel homozygous missense variant. The frameshift variant in Turkish cases may thus be a phenotype associated with renal failure in addition to the core phenotype associated with other OCLN gene variants, and such variants could be important for rapid molecular diagnosis and treatment. The frameshift variant in Turkish cases might also be investigated for both a potential founder effect and mutational hot spot.

Neurodevelopmental disorder with absent language and variable seizures (NEDALVS, OMIM # 618707) is a newly described autosomal dominant condition caused by heterozygous de novo mutation in WASF1 gene. WASF1 is a key component of the WAVE regulatory complex (WRC) required for actin polymerization. So far, only 3 distinct truncating variants clustering at the WCA domain, 3 missense variants localized to the meander region and a copy number variant (CNV) of WASF1 have been identified among 11 NEDALVS cases previously reported.We report a pediatric patient carrying novel de novo heterozygous missense variant (NM_003931.2: c.481T C, p.Trp161Arg) in WASF1 gene. During the first hospitalization at age of 5.5 months, the patient was initially diagnosed with infantile spasms, developmental delay (DD) and microcephaly due to nodding-like epileptic spasms in clusters and hypsarrhythmia on video-electroencephalography, lacking head control and body rollover, and abnormal head circumference 39 cm (-2SD). The genetic diagnosis with a causal WASF1 variant detected by trio exome sequencing indicated the rare NEDALVS.All the reported NEDALVS cases published in the PubMed English literature were reviewed to summarize the genetic and phenotypic spectrum of this novel disorder.We describe the third patient with a recurrently mutated amino acid site at p.Trp161 in WASF1, currently the 12th patient with NEDALVS. This hotspot missense variant and the truncating variants in WASF1 lead to similar phenotypic patterns with core features of severe DD/ID, and seizures, hypotonia, and microcephaly frequently observed. Our finding expands the WASF1 mutation spectrum and confirms the de novo hotspot missense variant at p.Trp161, further supporting the association of the novel NEDALVS with WASF1 gene and the actin regulatory pathway.

Background. Dengue Hemorrhagic Fever (DHF) is infection caused by Dengue Virus. Failure of vascularization is a main symptom of Dengue Hemorrhagic Fever inducing mediator secretion by an immune cell. Fc g RIIA and CCL2 have a significant role in dengue pathogenesis and possibility in having a chance to cause dengue with a worse manifestation. Objective. A nalysis of bio-informatic structure, function and expression of Fc g RIIA gene . Methods. Insilico analysis used NCBI database to find position and sequences. Analysis mutant use SNO and OMIM. Protein prediction withUniprot. Result. Fc g RIIA human with access number of NM_001136219 by a length of 2429 bp has its full name as Fc Fragment of IgG receptor IIa, located in 1q23.3 chromosom. analyzed mutation was rs1801274 with type of missense protein residue function experiencing a change from Histidin (H) turning into Arginin (R) with allele of wild-type A and becoming G amino acid position of 166 . there was structural difference of Fc g RIIA gene in wild type and mutant . Conclusion. Gene Fc g RIIA is a play a role of pathogenesis of dengue infection. Mutation in Fc g RIIA have polymorfisme at Dengue Hemorrage Fever

Severe malarial anemia (SMA) is a leading cause of childhood morbidity and mortality in holoendemic Plasmodium falciparum transmission regions. To gain enhanced understanding of predisposing factors for SMA, we explored the relationship between complement component 3 (C3) missense mutations [rs2230199 (2307C>G, Arg>Gly102) and rs11569534 (34420G>A, Gly>Asp1224)], malaria, and SMA in a cohort of children (n = 1617 children) over 36 months of follow-up. Variants were selected based on their ability to impart amino acid substitutions that can alter the structure and function of C3. The 2307C>G mutation results in a basic to a polar residue change (Arg to Gly) at position 102 (β-chain) in the macroglobulin-1 (MG1) domain, while 34420G>A elicits a polar to acidic residue change (Gly to Asp) at position 1224 (α-chain) in the thioester-containing domain. After adjusting for multiple comparisons, longitudinal analyses revealed that inheritance of the homozygous mutant (GG) at 2307 enhanced the risk of SMA (RR = 2.142, 95%CI: 1.229–3.735, P = 0.007). The haplotype containing both wild-type alleles (CG) decreased the incident risk ratio of both malaria (RR = 0.897, 95%CI: 0.828–0.972, P = 0.008) and SMA (RR = 0.617, 95%CI: 0.448–0.848, P = 0.003). Malaria incident risk ratio was also reduced in carriers of the GG (Gly102Gly1224) haplotype (RR = 0.941, 95%CI: 0.888–0.997, P = 0.040). Collectively, inheritance of the missense mutations in MG1 and thioester-containing domain influence the longitudinal risk of malaria and SMA in children exposed to intense Plasmodium falciparum transmission.

Introduction The VACTERL association is a rare malformation complex, showing at least three anomalies of the following organ systems: vertebra, anorectum, heart and vessels, trachea and esophagus, genitourinary tract, and limbs. In addition to a multifactorial event, congenital vascular disorders are also discussed as triggers for the VACTERL association. The aim of this study was to determine whether there is a genetic background for vascular disorders triggering VACTERL association. Materials and Methods We performed a functional analysis on whole exome sequencing data of 21 patients with VACTERL or VACTERL-like phenotype using the online analysis tool “Database for Annotation, Visualization and Integrated Discovery (DAVID) v6.8.” The study was approved by the institutional ethics committee (approval no. 026–13). Written informed consent was obtained from all patients or their parents. Results We identified a total of 86 genetic variants (in 75 genes) classified as damaging (including probably damaging missense, nonsense, and frameshift variants), which are associated to cardiovascular development. Each investigated patient showed at least one damaging variant in genes associated to cardiovascular development. These variants were further reduced by significance in cardiovascular development to 39 genetic variants (in 33 genes). Of note, a pair of siblings, both presenting with cardiac and renal defects, had the same damaging variant in two different genes. Conclusion Our results indicate a genetic background for congenital vascular disorders in patients with VACTERL association. In line with the literature, our data suggest that genetic mutation led to vascular diseases, which in turn may cause malformations similar to the VACTERL association.

X-linked hypohidrotic dysplasia (XLHED), caused by mutations in the EDA gene, is a rare genetic disease that affects the development and function of the teeth, hair, nails, and sweat glands. The structural and functional consequences of caused by an ectodysplasin-A (EDA) mutations on protein phenotype, stability, and posttranslational modifications (PTMs) have not been well investigated. The present investigation involves five missense mutations that cause XLHED (L56P, R155C, P220L, V251M, and V322A) in different domains of EDA (TM, furin, collagen, and tumor necrosis factor [TNF]) from previously published papers. The deleterious nature of EDA mutant variants was identified using several computational algorithm tools. The point mutations induce major drifts in the structural flexibility of EDA mutant variants and have a negative impact on their stability, according to the 3D protein modeling tool assay. Using the molecular docking technique, EDA/EDA variants were docked to 10 EDA interacting partners, retrieved from the STRING database. We found a novel biomarker CD68 by molecular docking analysis, suggesting all five EDA variants had lower affinity for EDAR, EDA2R, and CD68, implying that they would affect embryonic signaling between the ectodermal and mesodermal cell layers. In silico research such as gene ontology, subcellular localization, protein-protein interaction, and PTMs investigations indicates major functional alterations would occur in EDA variants. According to molecular simulations, EDA variants influence the structural conformation, compactness, stiffness, and function of the EDA protein. Further studies on cell line and animal models might be useful in determining their specific roles in functional annotations.

Autism spectrum disorders (ASDs) are a group of neurodevelopmental-related disorders with a high genetic risk. Recently, chromatin remodeling factors have been found to be related to ASDs. SMARCA4 is such a catalytic subunit of the chromatin-remodeling complex. In this report, we identified seven novel missense variants in the SMARCA4 gene from eight pediatric patients. All eight patients had moderate to severe intellectual disability, and seven showed autistic/likely autistic features. Compared with the patients reported in the literature, our patients were less likely to show craniofacial or finger/toe anomalies. Our findings further supported that SMARCA4 is associated with ASDs. We suggest that individuals with the abovementioned phenotypes should consider genetic testing.

Paget's disease of bone (PDB) is a rare metabolic bone disorder, which is extremely rare in Asian population. This study aimed to investigate the phenotypes and the pathogenic mutations of woman with early-onset PDB. The clinical features, bone mineral density, x-ray, radionuclide bone scan, and serum levels of alkaline phosphatase (ALP), procollagen type 1 N-terminal propeptide (P1NP), and β-carboxy-terminal cross-linked telopeptide of type 1 collagen (β-CTX) were measured in detail. The pathogenic mutations were identified by whole-exon sequencing and confirmed by Sanger sequencing. We also evaluated the effects of intravenous infusion of zoledronic acid on the bones of the patient and summarized the phenotypic characteristics of reported patients with mutation at position 155 of the valosin-containing protein (VCP). The patient only exhibited bone pain as the initial manifestation with vertebral compression fracture and extremely elevated ALP, P1NP, and β-CTX levels; she had no inclusion body myopathy and frontotemporal dementia. The missense mutation in exon 5 of the VCP gene (p.Arg155His) was identified by whole-exome sequencing and further confirmed by Sanger sequencing. No mutation in candidate genes of PDB, such as SQSTM1, CSF1, TM7SF4, OPTN, PFN1, and TNFRSF11A, were identified in the patient by Sanger sequencing. Rapid relief of bone pain and a marked decline in ALP, P1NP, and β-CTX levels were observed after zoledronic acid treatment. Previously reported patients with VCP missense mutation at position 155 (R155H) always had myopathy, frontotemporal dementia, and PDB, but the patient in this study exhibited only PDB. This was the first report of R155H mutation-induced early-onset in the VCP gene in Asian population. PDB was the only manifestation having a favorable response to zoledronic acid treatment. We broadened the genetic and clinical phenotype spectra of the VCP mutation.

Bosch–Boonstra–Schaaf optic atrophy syndrome (BBSOAS) is a rare congenital syndrome characterized by a range of phenotypes including optic atrophy and intellectual disability among other features. Pathogenic variants in the NR2F1 (nuclear receptor subfamily 2 group F member 1) gene have been linked to this condition. A recent report has shown that pathogenic variants in the start codon lead to decreased expression of the NR2F1 protein and a relatively mild phenotype, similar to that seen in whole gene deletions, and due to the lack of the dominant negative effect. Here we describe a severe case of BBSOAS with an initiation codon missense variant. The developmental delay, seizures, optic atrophy are in keeping with features observed in this condition, however this is the first report to describe colobomas and septo-optic dysplasia as associated features potentially extending the phenotype linked to BBSOAS. In addition, this is the first description of a severe phenotype linked to a de novo missense variant in the start codon of the NR2F1 gene.

Background:Salih myopathy, characterised by both congenital myopathy and fatal dilated cardiomyopathy, is an inherited muscle disorder that affects skeletal and cardiac muscles. TTN has been identified as the main cause of this myopathy, the enormous size of this gene poses a formidable challenge to molecular genetic diagnostics.Method:In the present study, whole-exome sequencing, cardiac MRI, and metabolic parameter assessment were performed to investigate the genetic causes of Salih myopathy in a consanguineous Iranian family who presented with titinopathy involving both skeletal and heart muscles in an autosomal recessive inheritance pattern.Results:Two missense variants of TTN gene (NM_001267550.2), namely c.61280A>C (p. Gln20427Pro) and c.54970G>A (p. Gly18324Ser), were detected and segregations were confirmed by polymerase chain reaction-based Sanger sequencing.Conclusions:The compound heterozygous variants, c.61280A>C, (p. Gln20427Pro) and c.54970G>A, (p. Gly18324Ser) in the TTN gene appear to be the cause of Salih myopathy and dilated cardiomyopathy in the family presented. Whole-exome sequencing is an effective molecular diagnostic tool to identify the causative genetic variants of large genes such as TTN.

PURPOSE To report a novel CRB1 variant responsible for autosomal recessive foveal retinoschisis and its associated clinical and electrophysiological data. METHODS A case report. RESULTS A 15-year-old boy has foveal retinoschisis similar to those seen in X-linked retinoschisis (XLRS). During follow-up, we observed the co-existence of foveoschitic changes and parafoveal macular atrophy. Molecular genetic testing identified compound heterozygous variants in the CRB1 gene, including a novel variant, c.3878 G > A, predicted to disrupt the normal translation of CRB1 and a previously reported likely pathogenic mutation, c.498_506del. Full-field electroretinograms (ERG) were normal but multifocal ERG showed focal reduced waveform amplitude corresponding to the area of atrophy. CONCLUSIONS A novel missense variant existing in a compound heterozygous state was identified. Biallelic CRB1 mutations can cause anatomical fovea disruption similar to XLRS but have very different electroretinogram findings. This case report enhances our understanding of the spectrum of biallelic CRB1 mutations.