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X-linked myopathy with excessive autophagy (XMEA) is a rare disorder characterized by slow progressive muscle weakness and distinctive pathology of excessive autophagic vacuoles on muscle biopsy. Here we report on five patients, in a single family, with proximal lower limb weakness. The proband, a 25-year-old man, presented with 5 years of progressive lower limbs proximal muscle weakness. His maternal grandfather and three of his maternal male cousins had similar clinical findings and were initially suspected to have Becker muscular dystrophy. Muscle biopsy in two affected family members demonstrated autophagic myopathy, and guided the genetic investigations to the identification of a pathogenic mutation, c.272G > C in the VMA21 gene, known to cause XMEA [1]. To the best of our knowledge this is the first identified Israeli Jewish family afflicted by XMEA.

OBJECTIVE: BCORL1, a transcriptional co-repressor, has a role in cortical migration, neuronal differentiation, maturation, and cerebellar development. We describe BCORL1 as a new genetic cause for major brain malformations. METHODS AND RESULTS: We report three patients from two unrelated families with neonatal onset intractable epilepsy and profound global developmental delay. Brain MRI of two siblings from the first family depicted hypoplastic corpus callosum and septal agenesis (ASP) in the older brother and unilateral perisylvian polymicrogyria (PMG) in the younger one. MRI of the patient from the second family demonstrated complete agenesis of corpus callosum (CC). Whole Exome Sequencing revealed a novel hemizygous variant in NM_021946.5 (BCORL1):c.796C>T (p.Pro266Ser) in the two siblings from the first family and the NM_021946.5 (BCORL1): c.3376G>A; p.Asp1126Asn variant in the patient from the second family, both variants inherited from healthy mothers. We reviewed the patients’ charts and MRIs and compared the phenotype to the other published BCORL1-related cases. Brain malformations have not been previously described in association with the BCORL1 phenotype. We discuss the potential influence of BCORL1 on brain development. CONCLUSIONS: We suggest that BCORL1 variants present with a spectrum of neurodevelopmental disorders and can lead to major brain malformations originating at different stages of fetal development. We suggest adding BCORL1 to the genetic causes of PMG, ASP, and CC dysgenesis.

ObjectiveTo determine the yield of genetic diagnoses using chromosomal microarray (CMA) and trio whole exome sequencing (WES), separately and combined, among patients with cryptogenic cerebral palsy (CP).MethodsTrio WES of patients with prior CMA analysis for cryptogenic CP, defined as disabling, non-progressive motor symptoms beginning before the age of 3 years without known cause.ResultsGiven both CMA analysis and trio WES, clinically significant genetic findings were identified for 58% of patients (26 of 45). Diagnoses were eight large CNVs detected by CMA and 18 point mutations detected by trio WES. None had more than one severe mutation. Approximately half of events (14 of 26) were de novo. Yield was significantly higher in patients with CP with comorbidities (69%, 22 of 32) than in those with pure motor CP (31%, 4 of 13; p=0.02). Among patients with genetic diagnoses, CNVs were more frequent than point mutations among patients with congenital anomalies (OR 7.8, 95% CI 1.2 to 52.4) or major dysmorphic features (OR 10.5, 95% CI 1.4 to 73.7). Clinically significant mutations were identified in 18 different genes: 14 with known involvement in CP-related disorders and 4 responsible for other neurodevelopmental conditions. Three possible new candidate genes for CP were ARGEF10, RTF1 and TAOK3.ConclusionsCryptogenic CP is genetically highly heterogeneous. Genomic analysis has a high yield and is warranted in all these patients. Trio WES has higher yield than CMA, except in patients with congenital anomalies or major dysmorphic features, but these methods are complementary. Patients with negative results with one approach should also be tested by the other.

Mucolipidosis type IV (MLIV; OMIM 252,650) is an autosomal recessive lysosomal disorder caused by mutations in MCOLN1. MLIV causes psychomotor impairment and progressive vision loss. The major hallmarks of postnatal brain MRI are hypomyelination and thin corpus callosum. Human brain pathology data is scarce and demonstrates storage of various inclusion bodies in all neuronal cell types. The current study describes novel fetal brain MRI and neuropathology findings in a fetus with MLIV. Fetal MRI was performed at 32 and 35 weeks of gestation due to an older sibling with spastic quadriparesis, visual impairment and hypomyelination. Following abnormal fetal MRI results, the parents requested termination of pregnancy according to Israeli regulations. Fetal autopsy was performed after approval of the high committee for pregnancy termination. A genetic diagnosis of MLIV was established in the fetus and sibling. Sequential fetal brain MRI showed progressive curvilinear hypointensities on T2-weighted images in the frontal deep white matter and a thin corpus callosum. Fetal brain pathology exhibited a thin corpus callosum and hypercellular white matter composed of reactive astrocytes and microglia, multifocal white matter abnormalities with mineralized deposits, and numerous aggregates of microglia with focal intracellular iron accumulation most prominent in the frontal lobes. This is the first description in the literature of brain MRI and neuropathology in a fetus with MLIV. The findings demonstrate prenatal white matter involvement with significant activation of microglia and astrocytes and impaired iron metabolism.

Contains fulltext : 231688.pdf (Publisher’s version ) (Closed access) PURPOSE: Pathogenic variants in the X-linked gene NEXMIF (previously KIAA2022) are associated with intellectual disability (ID), autism spectrum disorder, and epilepsy. We aimed to delineate the female and male phenotypic spectrum of NEXMIF encephalopathy. METHODS: Through an international collaboration, we analyzed the phenotypes and genotypes of 87 patients with NEXMIF encephalopathy. RESULTS: Sixty-three females and 24 males (46 new patients) with NEXMIF encephalopathy were studied, with 30 novel variants. Phenotypic features included developmental delay/ID in 86/87 (99%), seizures in 71/86 (83%) and multiple comorbidities. Generalized seizures predominated including myoclonic seizures and absence seizures (both 46/70, 66%), absence with eyelid myoclonia (17/70, 24%), and atonic seizures (30/70, 43%). Males had more severe developmental impairment; females had epilepsy more frequently, and varied from unaffected to severely affected. All NEXMIF pathogenic variants led to a premature stop codon or were deleterious structural variants. Most arose de novo, although X-linked segregation occurred for both sexes. Somatic mosaicism occurred in two males and a family with suspected parental mosaicism. CONCLUSION: NEXMIF encephalopathy is an X-linked, generalized developmental and epileptic encephalopathy characterized by myoclonic-atonic epilepsy overlapping with eyelid myoclonia with absence. Some patients have developmental encephalopathy without epilepsy. Males have more severe developmental impairment. NEXMIF encephalopathy arises due to loss-of-function variants.

Acyl‐CoA dehydrogenase family member 9 (ACAD9) is an enzyme essential for the assembly of mitochondrial respiratory chain complex I. ACAD9 deficiency can cause lactic acidosis, myopathy, cardiomyopathy, intellectual disability, and early demise. We present a patient with mitochondrial myopathy, hypertrophic cardiomyopathy, and epilepsy due to recessive ACAD9 mutations. A muscle biopsy depicted ragged red fibers, and decreased activity of complex I of the respiratory chain. Treatment with riboflavin was initiated at the age of 4 years due to complex I deficiency (before the genetic diagnosis), resulting in symptomatic improvement of the cardiomyopathy, exercise intolerance, and lactate levels. A novel homozygous ACAD9 mutation was found: c.398G>A; p.Ser133Asn at the age of 23 years. Three years later she sustained a normal pregnancy, and gave birth to a healthy baby girl delivered by an elective Cesarean section. To the best of our knowledge, this is the first description of a successful pregnancy and delivery in a patient with this rare mitochondrial disease.

Iron-sulfur cluster assembly 2 (ISCA2)-related multiple mitochondrial dysfunction syndrome 4 (MMDS4) is a fatal autosomal recessive mitochondrial leukoencephalopathy. The disease typically manifests with rapid neurodevelopmental deterioration during the first months of life leading to a vegetative state and early death. MRI demonstrates a demyelinating leukodystrophy. We describe an eleven-year-old boy with a milder phenotype of ISCA2 related disorder manifesting as: normal early development, acute infantile neurologic deterioration leading to stable spastic quadriparesis, optic atrophy and mild cognitive impairment. The first MRI demonstrated a diffuse demyelinating leukodystrophy. A sequential MRI revealed white matter rarefaction with well-delineated cysts. The patient harbors two novel bi-allelic variants (p.Ala2Asp and p.Pro138Arg) in ISCA2 inherited from heterozygous carrier parents. This report expands the clinical spectrum of ISCA2-related disorders to include a milder phenotype with a longer life span and better psychomotor function and cavitating leukodystrophy on MRI. We discuss the possible genetic explanation for the different presentation.

Objective The purpose of this study was to establish prognostic factors in fetuses diagnosed with periventricular pseudocysts (PVPCs) without known congenital infection, between 28 and 37 weeks of gestation. Methods This retrospective study included cases of fetal PVPC from 2008 to 2018. PVPCs were classified according to location, number, extension, morphology, and size. Additional findings, MRI and genetic studies were recorded. Pregnancy outcome, postnatal, or postmortem results were obtained. Images from patients with normal (Group 1) and abnormal postnatal development (Group 2) were compared for analysis of factors predictive of outcome. Results One-hundred and fifteen pseudocysts were observed in 59 patients. In 34 fetuses (57%), the PVPC was an isolated finding. Thirty-nine patients delivered live newborns, 27% opted for termination of pregnancy, and 4 patients were lost to follow-up. Eighty-four percent of the liveborns had normal development. When assessing for the influence of pseudocyst characteristics, a wide CSP, or large head circumference, neither of these affected the outcome. The presence of additional anomalies was the only positive predictor for abnormal development regradless of specific PVPC characteristics (P = .002). Conclusions In fetuses with PVPCs, the presence of additional anomalies was the only predictor for adverse postnatal outcome. No association between cystic characteristics and adverse outcome was observed.

Objective To describe fetal, clinical, radiological, morphological features of TUBB3 related syndrome. Methods We report two families each of two generations harboring a novel and a previously described heterozygous TUBB3 pathogenic variants. We compared these patients with other published TUBB3-related cases. We describe the pathological features of dysgyria in the two aborted fetuses. Results The mother and son from family 1 had a history of mild developmental delay in motor and language skills and demonstrated mild cerebellar signs and mirror movements. Neuroimaging findings included: hypoplastic corpus callosum (CC), asymmetric ventriculomegaly and cerebellar vermis hypoplasia in all patients and frontal dysgyria in three. Autopsy of the fetal brain showed an unusual shape and orientation of the frontal sulci and gyri with normal cortical layering and no abnormal cell types. The mother of family 2 had congenital strabismus, mild muscle weakness on the right and a past history of developmental delay. Fetal brain MRI showed abnormal cerebral sulcation, hemispheric asymmetry, asymmetric ventriculomegaly, dysmorphic short CC and frontal cortical interdigitation. Autopsy demonstrated fronto-parietal predominant dysgyria, bilateral ventriculomegaly, hippocampal and CC hypoplasia, abnormal Sylvian fissure. Lamination and neuron morphology in the areas of dysgyria were normal. Conclusions TUBB3 related cortical malformations can be mild, consistent with dysgyria rather than typical pachygyria or polymicrogyria. The autopsy findings in fetal TUBB3 related dysgyria are abnormal orientation of sulci and gyri, but normal neuron morphology and layering. We suggest that TUBB3 – associated brain malformations can be suspected in-utero which in turn can aid in prognostic counselling and interpretation of genetic testing.

The human WW Domain Containing Oxidoreductase (WWOX) gene was originally described as a tumor suppressor gene. However, recent reports have demonstrated its cardinal role in the pathogenesis of central nervous systems disorders such as epileptic encephalopathy, intellectual disability, and spinocerebellar ataxia. We report on six patients from three unrelated families of full or partial Yemenite Jewish ancestry exhibiting early infantile epileptic encephalopathy and profound developmental delay. Importantly, four patients demonstrated facial dysmorphism. Exome sequencing revealed that four of the patients were homozygous for a novel WWOX c.517-2A > G splice-site variant and two were compound heterozygous for this variant and a novel c.689A > C, p.Gln230Pro missense variant. Complementary DNA sequencing demonstrated that the WWOX c.517-2A > G splice-site variant causes skipping of exon six. A carrier rate of 1:177 was found among Yemenite Jews. We provide the first detailed description of patients harboring a splice-site variant in the WWOX gene and propose that the clinical synopsis of WWOX related epileptic encephalopathy should be broadened to include facial dysmorphism. The increased frequency of the c.517-2A > G splice-site variant among Yemenite Jews coupled with the severity of the phenotype makes it a candidate for inclusion in expanded preconception screening programs.

The chromosome alignment maintaining phosphoprotein 1 (CHAMP1) gene has a key role in neurodevelopment. It is involved in kinetochore-microtubule attachment and in the regulation of chromosomes alignment during mitosis. So far, 17 cases of CHAMP1 mutations have been reported with a common clinical picture of developmental delay and intellectual disability, dysmorphic facial features, hypotonia and/or spasticity, and microcephaly. Four patients had epilepsy of whom three had focal seizures and one had generalized epilepsy. We report two new cases, which have in addition to developmental delay, refractory myoclonic epilepsy. These cases suggest that the phenotypic spectrum of CHAMP1 mutations may be broader and includes refractory myoclonic epilepsy as well.

Protein arginine methyltransferase 7 (PRMT7) is a member of a family of enzymes that catalyze the transfer of methyl groups from S-adenosyl-l-methionine to nitrogen atoms on arginine residues. Arginine methylation is involved in multiple biological processes, such as signal transduction, mRNA splicing, transcriptional control, DNA repair, and protein translocation. Currently, 10 patients have been described with mutations in PRMT7. The shared findings include: hypotonia, intellectual disability, short stature, brachydactyly, and mild dysmorphic features. We describe the prenatal, postnatal, and pathological findings in two male sibs homozygote for a mutation in PRMT7. Both had intrauterine growth restriction involving mainly the long bones. In addition, eye tumor was found in the first patient, and nonspecific brain calcifications and a systemic venous anomaly in the second. The pregnancy of the first child was terminated and we describe the autopsy findings. The second child had postnatal growth restriction of prenatal onset, hypotonia, strabismus, sensorineural hearing loss, genitourinary and skeletal involvement, and global developmental delay. He had dysmorphic features that included frontal bossing, upslanting palpebral fissures, small nose with depressed nasal bridge, and pectus excavatum. Our patients provide additional clinical and pathological data and expand the phenotypic manifestations associated with PRMT7 homozygote/compound heterozygote mutations to include brain calcifications and delayed myelination, and congenital orbital tumor.

In 2003, a new syndrome was described in the Sephardi Jewish population, named progressive cerebello-cerebral atrophy (PCCA) based on the typical neuroradiological findings. Following the identification of the causal genes in 2010 and 2014, two types were defined: PCCA type 1 due to SEPSECS mutations and PCCA type 2 due to VPS53 mutations. Progressive encephalopathy with edema, hypsarrhythmia and optic atrophy (PEHO) was described in 1991 in Finland. The clinical and radiological phenotype resembles PCCA. The genetic background has been elusive for many years. Recently, mutations in multiple genes including SEPSECS have been described in patients with a PEHO-like syndrome. In 2007 two siblings of Moroccan-Jewish origin were diagnosed as having PEHO due to a severe developmental encephalopathy, limb and facial edema, intractable epilepsy, optic atrophy in one sibling and dysmorphic features. Six years ago an extensive workup, including whole exome sequencing, did not reveal the cause. Recently, a clinical reevaluation of the siblings suggested the possibility that they suffer from PCCA. A reanalysis of the exome data from 2014 revealed that the siblings indeed carried the two VPS53 mutations (exon 19 c.2084A>G p.(Gln695Arg) and c.1556 + 5G>A) and the parents were found to be carriers. The discovery that mutations in both VPS53 and SEPSECS can present with a PEHO-like phenotype, place PCCA and PEHO on the same clinical spectrum and suggest they may be allelic syndromes.

OBJECTIVES To describe the prenatal neuroimaging spectrum of rhombencephalosynapsis (RES) and criteria for its classification according to the severity of vermian anomaly. METHODS In this multicenter retrospective study of fetuses with RES between 2002 and 2020, the medical records and brain ultrasound and magnetic resonance images were evaluated comprehensively to determine the severity of the vermian anomaly and the presence of associated brain findings. RES was classified, according to the pattern of vermian agenesis and the extent of the fusion of the hemispheres, as complete RES (complete absence of the vermis) or partial RES (further classified according to the part of the vermis that was missing and, consequently, the region of hemispheric fusion, as anterior, posterior, severe or mixed RES). Findings were compared between cases with complete and those with partial RES. RESULTS Included in the study were 62 fetuses with a gestational age ranging between 12 and 37 weeks. Most had complete absence of the vermis (complete RES, 77.4% of cases), a 'round-shaped' cerebellum on axial views (72.6%) and a transverse cerebellar diameter (TCD)

BACKGROUND: CACNA1A-related disorders present with persistent progressive and non-progressive cerebellar ataxia and paroxysmal events: epileptic seizures and non-epileptic attacks. These phenotypes overlap and co-exist in the majority of patients.OBJECTIVE: To describe phenotypes in infantile onset CACNA1A-related disorder and to explore intra-familial variations and genotype-phenotype correlations.MATERIAL AND METHODS: This study was a multicenter international collaboration. A retrospective chart review of CACNA1A patients was performed. Clinical, radiological, and genetic data were collected and analyzed in 47 patients with infantile-onset disorder.RESULTS: Paroxysmal non-epileptic events (PNEE) were observed in 68% of infants, with paroxysmal tonic upward gaze (PTU) noticed in 47% of infants. Congenital cerebellar ataxia (CCA) was diagnosed in 51% of patients including four patients with developmental delay and only one neurological sign. PNEEs were found in 63% of patients at follow-up, with episodic ataxia (EA) in 40% of the sample. Cerebellar ataxia was found in 58% of the patients at follow-up. Four patients had epilepsy in infancy and nine in childhood. Seven infants had febrile convulsions, three of which developed epilepsy later; all three patients had CCA. Cognitive difficulties were demonstrated in 70% of the children. Cerebellar atrophy was found in only one infant but was depicted in 64% of MRIs after age two.CONCLUSIONS: Nearly all of the infants had CCA, PNEE or both. Cognitive difficulties were frequent and appeared to be associated with CCA. Epilepsy was more frequent after age two. Febrile convulsions in association with CCA may indicate risk of epilepsy in later childhood. Brain MRI was normal in infancy. There were no genotype-phenotype correlations found.

The clinical presentation of bilateral perisylvian polymicrogyria (PMG) is highly variable, including oromotor dysfunction, epilepsy, intellectual disability, and pyramidal signs. Extrapyramidal features are extremely rare. We present four apparently unrelated patients with a unique association of PMG with dystonia. The clinical, genetic, and radiologic features are described and possible mechanisms of dystonia are discussed. All patients were female and two were born to consanguineous families. All presented with early childhood onset dystonia. Other neurologic symptoms and signs classically seen in bilateral perisylvian PMG were observed, including oromotor dysfunction and speech abnormalities ranging from dysarthria to anarthria (4/4), pyramidal signs (3/4), hypotonia (3/4), postnatal microcephaly (1/4), and seizures (1/4). Neuroimaging showed a unique pattern of bilateral PMG with an infolded cortex originating primarily from the perisylvian region in three out of four patients. Whole exome sequencing was performed in two out of four patients and did not reveal pathogenic variants in known genes for cortical malformations or movement disorders. The dystonia seen in our patients is not described in bilateral PMG and suggests an underlying mechanism of impaired connectivity within the motor network or compromised cortical inhibition. The association of bilateral PMG with dystonia in our patients may represent a new neurogenetic disorder.

IFIH1 gain-of-function has been reported as a cause of a type I interferonopathy encompassing a spectrum of autoinflammatory phenotypes including Aicardi-Goutieres syndrome and Singleton Merten syndrome. Ascertaining patients through a European and North American collaboration, we set out to describe the molecular, clinical and interferon status of a cohort of individuals with pathogenic heterozygous mutations in IFIH1. We identified 74 individuals from 51 families segregating a total of 27 likely pathogenic mutations in IFIH1. Ten adult individuals, 13.5% of all mutation carriers, were clinically asymptomatic (with seven of these aged over 50 years). All mutations were associated with enhanced type I interferon signaling, including six variants (22%) which were predicted as benign according to multiple in silico pathogenicity programs. The identified mutations cluster close to the ATP binding region of the protein. These data confirm variable expression and nonpenetrance as important characteristics of the IFIH1 genotype, a consistent association with enhanced type I interferon signaling, and a common mutational mechanism involving increased RNA binding affinity or decreased efficiency of ATP hydrolysis and filament disassembly rate. Yanick J. Crow acknowledges The University of Maryland Brain and Tissue Bank of the NIH NeuroBioBank. Yanick J. Crow acknowledges the European Research Council (786142-E-T1IFNs), a state subsidy managed by the National Research Agency (France) under the "Investments for the Future" program bearing the reference ANR-10-IAHU-01 and the MSDAvenir fund (DEVO-DECODE Project). Tracy A. Briggs acknowledges the National Institute for Health Research (NIHR; NIHR Transitional Research Fellowship, TRF-2016-09-002; with the views expressed were those of the author and not necessarily those of the NHS, the NIHR or the Department of Health). Adeline L. Vanderver is supported by the Kamens endowed chair for Translational Neurotherapeutics and the Myelin Disorders Bioregistry Project. Adeline L. Vanderver and Laura A. Adang acknowledge the CURE Pennsylvania Frontiers in Leukodystrophy grant and U01HD082806. Laura A. Adang also acknowledges the National Center for Advancing Translational Sciences of the National Institutes of Health under award number KL2TR001879. Lien Van Eyck received funding from Research Foundation Flanders (FWO).

BackgroundDe novo mutations in PURA have recently been described to cause PURA syndrome, a neurodevelopmental disorder characterised by severe intellectual disability (ID), epilepsy, feeding difficulties and neonatal hypotonia.ObjectivesTo delineate the clinical spectrum of PURA syndrome and study genotype-phenotype correlations.MethodsDiagnostic or research-based exome or Sanger sequencing was performed in individuals with ID. We systematically collected clinical and mutation data on newly ascertained PURA syndrome individuals, evaluated data of previously reported individuals and performed a computational analysis of photographs. We classified mutations based on predicted effect using 3D in silico models of crystal structures of Drosophila-derived Pur-alpha homologues. Finally, we explored genotype-phenotype correlations by analysis of both recurrent mutations as well as mutation classes.ResultsWe report mutations in PURA (purine-rich element binding protein A) in 32 individuals, the largest cohort described so far. Evaluation of clinical data, including 22 previously published cases, revealed that all have moderate to severe ID and neonatal-onset symptoms, including hypotonia (96%), respiratory problems (57%), feeding difficulties (77%), exaggerated startle response (44%), hypersomnolence (66%) and hypothermia (35%). Epilepsy (54%) and gastrointestinal (69%), ophthalmological (51%) and endocrine problems (42%) were observed frequently. Computational analysis of facial photographs showed subtle facial dysmorphism. No strong genotype-phenotype correlation was identified by subgrouping mutations into functional classes.ConclusionWe delineate the clinical spectrum of PURA syndrome with the identification of 32 additional individuals. The identification of one individual through targeted Sanger sequencing points towards the clinical recognisability of the syndrome. Genotype-phenotype analysis showed no significant correlation between mutation classes and disease severity.

Biallelic mutations in IBA57 cause a mitochondrial disorder with a broad phenotypic spectrum that ranges from severe intellectual disability to adolescent-onset spastic paraplegia. Only 21 IBA57 mutations have been reported, therefore the phenotypic spectrum of IBA57-related mitochondrial disease has not yet been fully elucidated. In this study, we performed whole-exome sequencing on a Sepharadi Jewish and Japanese family with leukodystrophy. We identified four novel biallelic variants in IBA57 in the two families: one frameshift insertion and three missense variants. The three missense variants were predicted to be disease-causing by multiple in silico tools. The 29-year-old Sepharadi Jewish male had infantile-onset optic atrophy with clinically asymptomatic leukodystrophy involving periventricular white matter. The 19-year-old younger brother, with the same compound heterozygous IBA57 variants, had a similar clinical course until 7 years of age. However, he then developed a rapidly progressive spastic paraparesis following a febrile illness. A 7-year-old Japanese girl had developmental regression, spastic quadriplegia, and abnormal periventricular white matter signal on brain magnetic resonance imaging performed at 8 months of age. She had febrile convulsions at the age of 18 months and later developed epilepsy. In summary, we have identified four novel IBA57 mutations in two unrelated families. Consequently, we describe a patient with infantile-onset optic atrophy and asymptomatic white matter involvement, thus broadening the phenotypic spectrum of biallelic IBA57 mutations.

RASopathies are a group of rare, clinically related conditions affecting development and growth, and are caused by germline mutations in genes encoding signal transducers and modulators with a role in the RAS signaling network. These disorders share facial dysmorphia, short stature, variable cognitive deficits, skeletal and cardiac defects, and a variable predisposition to malignancies. Here, we report on a de novo 10-nucleotide-long deletion in HRAS (c.481_490delGGGACCCTCT, NM_176795.4; p.Leu163ProfsTer52, NP_789765.1) affecting transcript processing as a novel event underlying a RASopathy characterized by developmental delay, intellectual disability and autistic features, distinctive coarse facies, reduced growth, and ectodermal anomalies. Molecular and biochemical studies demonstrated that the deletion promotes constitutive retention of exon IDX, which is generally skipped during HRAS transcript processing, and results in a stable and mildly hyperactive GDP/GTP-bound protein that is constitutively targeted to the plasma membrane. Our findings document a new mechanism leading to altered HRAS function that underlies a previously unappreciated phenotype within the RASopathy spectrum.

Objective To explore the risk for abnormal chromosomal microarray analysis (CMA) findings in pregnancies with oligohydramnios. Methods Data from all CMA analyses performed due to oligohydramnios between 2013 and 2017 were retrospectively obtained from the Israeli Ministry of Health database. The rate of clinically significant (pathogenic and likely pathogenic) findings was compared to a local cohort of pregnancies with normal ultrasound, yielding a 1.4% rate of abnormal CMA results. In addition, a search was conducted through the PubMed database addressing the issue. Results Fifty CMA analyses were performed due to oligohydramnios. The 2% risk for clinically significant CMA finding in pregnancies with oligohydramnios did not differ from the control population of 5541 pregnancies with normal ultrasound – relative risk (RR) 1.4 [95% confidence interval (CI) 0.2–10.2]. Literature search yielded 394 titles, of which four relevant articles were selected, all using fetal karyotyping. Conclusion There is yet insufficient evidence to support invasive prenatal testing in pregnancies with isolated oligohydramnios.

Roughly 40 genes have been linked to autosomal recessive (AR) ataxia syndromes. Of these, at least 10 encode gene products localizing to the mitochondrion. tRNA-histidine guanylyltransferase 1 like (THG1L) localizes to the mitochondrion and catalyzes the 3′–5′ addition of guanine to the 5′-end of tRNA-histidine. Previously, three siblings with early onset cerebellar dysfunction, developmental delay, pyramidal signs, and cerebellar atrophy on brain magnetic resonance imaging (MRI) were reported to carry homozygous V55A mutations in THG1L. Fibroblasts derived from these individuals showed abnormal mitochondrial networks when subjected to obligatory oxidative phosphorylation. A carrier rate of 0.8%, but no THG1L V55A homozygotes, was found in a cohort of 3,232 unrelated Ashkenazi Jewish individuals, and no homozygotes were found in Exac or gnomAD. This variant is reported with an allelic frequency of 0.02% in Exac, and is not listed in gnomAD. A similar phenotype was recently reported for another, homozygous variant p.L294P was reported with a similar, but more severely affected phenotype [Shaheen et al. (2019); Genetics in Medicine 21: 545–552]. Here, we report two additional Ashkenazi Jewish patients, carrying the same homozygous V55A mutation. We present bioinformatic analyses of the V55A mutation demonstrating high conservation in metazoan species. We refine the clinical and radiological phenotype and discuss the uniqueness of the clinical course of this novel mitochondrial AR ataxia in comparison to the diverse molecular etiologies and clinical phenotypes of other known mitochondrial AR ataxias.

Adenylosuccinate lyase deficiency is a rare autosomal recessive disorder of purine metabolism. The disorder manifests with developmental delay, postnatal microcephaly, hypotonia, involuntary movements, epileptic seizures, ataxia and autistic features. Paroxysmal non-epileptic motor events are not a typical presentation of the disease. We describe an 8-year-old boy who presented with an infantile onset of prolonged episodes of multifocal sustained myoclonic tremor lasting from minutes to days on a background of global developmental delay and gait ataxia. Ictal EEG during these episodes was normal. Ictal surface EMG of the involved upper limb showed a muscular activation pattern consistent with cortical myoclonus. Brain MRI showed mild cerebral atrophy. Whole exome sequencing revealed a novel homozygous variant in the ADSL gene: c.1027G > A; p. Glu343Lys, inherited from each heterozygous parent. There was a marked elevation of urine succinyladenosine, confirming the diagnosis of adenylosuccinate lyase deficiency. In conclusion, myoclonic tremor status expands the spectrum of movement disorders seen in adenylosuccinate lyase deficiency.

Objective To evaluate the prediction of microcephaly at birth (micB) using established and two new reference ranges for fetal head circumference (HC) and to assess whether integrating additional parameters can improve prediction. Methods Microcephaly in utero was defined as a fetal HC 3SD below the mean for gestational age according to Jeanty et al.'s reference range. The records of cases with fetal microcephaly (Fmic) were evaluated for medical history, imaging findings, biometry and postnatal examination/autopsy findings. Microcephaly was confirmed at birth (micB) by an occipitofrontal circumference (OFC) or a brain weight at autopsy 2SD below the mean for gestational age. The new INTERGROWTH-21st Project and a recent Israeli reference for fetal growth were applied for evaluation of the Fmic positive predictive value (PPV) for diagnosis of micB cases. Optimal HC cut-offs were determined for each of the new references with the aim of detecting all micB cases whilst minimizing the number of false positives found to have a normal HC at birth. We also assessed the difference between the Z-scores of the prenatal HC and the corresponding OFC at birth, the frequency of small-for-gestational age (SGA), decreased HC/abdominal circumference (AC) and HC/femur length (FL) ratios, the prevalence of associated malformations and family history. Results Forty-two fetuses were diagnosed as having Fmic according to the Jeanty reference, but micB was confirmed in only 24 (PPV, 57.1%). The optimal INTERGROWTH and Israeli reference HC cut-offs for micB diagnosis were mean – 3SD and mean – 2.3SD, resulting in a statistically non-significant improvement in PPV to 61.5% and 66.7%, respectively. The presence of a family history of microcephaly, SGA, associated malformations and application of stricter HC cut-offs resulted in a higher PPV of micB, although not statistically significant and with a concurrent increase in the number of false-negative results. The deviation of the HC from the mean, by all references, was significantly larger compared with the actual deviation of the OFC at birth, with mean differences between the corresponding Z-scores of −1.15, −1.95 and −0.74 for the Jeanty, INTERGROWTH and Israeli references, respectively. Conclusions The evaluated reference ranges all result in considerable over-diagnosis of fetal microcephaly. The use of the two new HC reference ranges did not significantly improve micB prediction compared with that of Jeanty et al., whilst use of additional characteristics and stricter HC cut-offs could improve the PPV with an increase in false negatives. The postnatal OFC deviates significantly less from the mean compared with the prenatal HC, and we propose that adjustment for this would enable better prediction of the actual OFC deviation at birth. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Objective Early onset epileptic encephalopathies (EOEEs) are a group of devastating diseases, manifesting in the first year of life with frequent seizures and/or prominent interictal epileptiform discharges on the electroencephalogram (EEG), developmental delay/regression and usually a poor prognosis. There are numerous causes for EOEEs making the diagnostic workup time consuming and costly. We describe the diagnostic workup in two siblings with EOEE, profound global developmental delay (GDD) and post natal microcephaly. Neuro-imaging disclosed non-specific progressive cerebral atrophy. Methods Whole-exome sequencing analysis. Results Two causative mutations in the gene encoding for mitochondrial arginyl-transfer RNA synthetase, RARS2, were found. This gene is presently related to ponto-cerebellar hypoplasia (PCH) type 6. Reviewing our cases and 16 others published, a common phenotype emerges of EOEE with onset in the immediate post natal or early infantile period (range 1 day-4 months). Many children had more than one seizure type; the most frequent types were myoclonic (50%) followed by clonic (31.5%). The seizures were described as multifocal/alternating sides in 37.5%. Initial EEG demonstrated slowing of the background in 62.5% and epileptiform discharges in 50%. EEG was reported as initially normal in 19%, but almost all the following recordings showed deterioration. Few patients demonstrated initial response to an anti-epileptic drug but eventually all but one had intractable epilepsy. All patients displayed profound GDD – none attained any significant milestones. Most patients had normal occipito-frontal circumference at birth, but almost all developed progressive microcephaly, up to –6 standard deviations. The most common radiological finding was progressive cerebral (100%) and cerebellar (93%) atrophy and NOT progressive PCH (present in 67%). The condition proved to be fatal in 50%. Conclusion We suggest that RARS2 gene mutations can cause a metabolic neurodegenerative disease manifesting primarily as EOEE with post natal microcephaly, without the distinctive radiological feature of PCH.

Objective To construct a reference range for a new vertical measurement of the fetal head and to assess whether its combination with fetal head circumference (HC) can prevent the misdiagnosis of microcephaly in fetuses with an acrocephalic-like head deformation. Methods A new vertical cranial biometric measurement was defined: the foramen magnum-to-cranium distance (FCD), measured between the foramen magnum and the upper inner cranial border along the posterior wall of the brainstem. The measurement was performed in a precise mid-sagittal plane using a three-dimensional multiplanar display of a sagittally acquired sonographic volume of the fetal head. The normal reference range was developed by measuring 396 healthy fetuses of low-risk singleton pregnancies between 15 and 40 gestational weeks. This reference was applied to 25 fetuses with microcephaly diagnosed prenatally (Fmic) based on HC ≥ 3 SD below the mean for gestational age. We determined an optimal FCD cut-off for combination with HC to detect all cases found with microcephaly at birth (micB), while excluding the fetuses with normal head circumference at birth (NHCB), who were described postnatally as having an acrocephalic-like cranial deformation. Results In the healthy singleton fetuses, FCD increased with gestational age, with a quadratic equation providing an optimal fit to the data (adjusted R2 = 0.934). The measurement could be assessed in 95.2% of cases. Of the 25 cases diagnosed with Fmic prenatally, on the basis of HC alone, 14 were micB and 11 were NHCB. We observed FCD below the mean – 2SD for gestational age in all 14 micB cases, but in only four of the 11 NHCB cases (P < 0.003). An acrocephalic-like cranial deformation was described at birth in five of the seven NHCB cases with normal FCD. The mean ± SD FCD Z-score of the micB cases was significantly lower (P < 0.001) than that of the false-positive ones: −3.85 ± 0.96 SD and −1.59 ± 1.45 SD, respectively. Based on HC measurement alone, the positive predictive value (PPV) was 56%. Combination of the HC and FCD criteria raised the PPV to 78%, decreasing the number of false positives from 11 to four, without missing any of the 14 micB cases. Conclusions Fetal vertical cranial biometric assessment in the mid-sagittal plane is feasible and correlates well with gestational age. In our series, a vertical cranial deformation was a frequent cause of a false Fmic diagnosis made on the basis of HC alone. Combination of the new vertical cranial biometric measurement with HC measurement can exclude these cases and thus improve diagnostic accuracy for Fmic. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Introduction: The prenatal diagnosis of fetal craniosynostosis is challenging, especially in single-suture cases. When sutures are obliterated, sound waves fail to penetrate the cortical bone, creating an evident acoustic shadow on the underlying brain. The objective of this study was to evaluate the yield of the ‘brain shadowing sign' (BSS) as a novel sonographic marker for craniosynostosis. Subjects and Methods: Patients with an antenatal diagnosis of fetal craniosynostosis (cases) and healthy controls paired for gestational age were enrolled in this retrospective case-control study. Two-dimensional scans were assessed by three examiners for the presence of the BSS and additional fetal findings. Results: The BSS was clearly depicted in all 24 cases on the first analysis and in 22 cases on the second analysis. No fetus from the control group (n = 48) presented the BSS in any of the analyses. Fifteen cases had isolated craniosynostosis and 9 were syndromic (Apert, Saethre-Chotzen and craniofrontonasal syndromes), which were diagnosed significantly earlier due to additional malformations. Discussion: The BSS is a novel sonographic marker of craniosynostosis which can be used to increase the diagnostic rate of this rare condition and does not require the use of high-definition three-dimensional transducers to be depicted.

Agenesis of the corpus callosum is currently diagnosed prenatally with ultrasound and MRI. While the diagnostic aspects of callosal defects are widely addressed, anatomo-histological data from fetal autopsies are sparse. Callosal defects were present in 50 fetal autopsies. Four distinct groups of complete, partial, hypoplastic, and mixed defects were determined by the gross and histologic details of the corpus callosum. These details helped to rule out other midline defects such as holoprosencephaly. Additional autopsy findings enabled specific diagnoses and suggested etiopathogeneses. Hypoplastic and mixed defects were associated with more abnormalities of the cerebral hemispheres and internal organs. The four groups did not differ according to gender, external dysmorphism, or cerebellar and brainstem anomalies. Defects were classified as syndromic (68 %), encephaloclastic (8 %), undetermined (14 %), or isolated (10 %) based on the autopsy findings. Isolated agenesis of the corpus callosum was diagnosed in only 10 % of the cases in this series, compared to higher numbers diagnosed by prenatal ultrasonography and MRI. Therefore, the autopsy, through its detailed, careful evaluation of external, as well as gross and histological internal features, can elucidate the etiopathogenesis of agenesis of the corpus callosum and suggest specific diagnoses which cannot be ascertained by prenatal imaging.

Pontocerebellar hypoplasia (PCH) encompasses a group of neurodegenerative disorders. There are ten known subtypes with common characteristics of pontine and cerebellar hypoplasia or atrophy, neocortical atrophy, and microcephaly. PCH is associated with anterior horn cell degeneration in PCH1a and PCH1b due to mutations in the VRK1 and EXOSC3 genes. Late onset PCH1 has been described in single case reports. The molecular etiology remains mostly unknown. We describe two siblings from a consanguineous Moslem Arabic family with a unique combination of progressive cerebellar atrophy and a SMA-like anterior horn cell degeneration due to a homozygous mutation in the PLA2G6 gene (NM_003560.2). The PLA2G6 gene encodes phospholipase A2 beta, which is involved in the remodeling of membrane phospholipids, signal transduction and calcium signaling, cell proliferation and apoptosis. Mutations in PLA2G6 are known to cause Neurodegeneration with brain iron accumulation 2 (NBIA2): Our patients have some similarities with NBIA2; both are characterized by rapidly progressive psychomotor regression and cerebellar atrophy. However, NBIA2 is not known to exhibit anterior horn cell degeneration. Our patients' phenotype is more consistent with late onset PCH1; thus, indicating that the spectrum of clinical and radiological presentations of PLA2G6 mutations should be extended and that this gene should be included in the molecular evaluation of patients with late onset PCH1.

OPA1 related disorders include: classic autosomal dominant optic atrophy syndrome (ADOA), ADOA plus syndrome and a bi-allelic OPA1 complex neurological disorder. We describe metabolic stroke in a patient with bi-allelic OPA1 mutations. A twelve-year old girl presented with a complex neurological disorder that includes: early onset optic atrophy at one year of age, progressive gait ataxia, dysarthria, tremor and learning impairment. A metabolic stroke occurred at the age of 12 years. The patient was found to harbor a de novo heterozygous frame shift mutation c.1963_1964dupAT; p.Lys656fs (NM_015560.2) and a missense mutation c.1146A > G; Ile382Met (NM_015560.2) inherited from her mother. The mother, aunt, and grandmother are heterozygous for the Ile382Met mutation and are asymptomatic. The co-occurrence of bi-allelic mutations can explain the severity and the early onset of her disease. This case adds to a growing number of patients recently discovered with bi-allelic OPA1 mutations presenting with a complex and early onset neurological disorder resembling Behr syndrome. To the best of our knowledge metabolic stroke has not been described before as an OPA1 related manifestation. It is important to be aware of this clinical feature for a prompt diagnosis and consideration of available treatment.

Objectives To describe a unique posterior fossa neuroimaging characteristic of prenatal PHACES syndrome (PS): unilateral cerebellar hypoplasia (UCH) and ipsilateral posterior fossa (PF) cyst communicating with an asymmetrically distended 4th ventricle. Methods The registries of seven prenatal diagnosis centers were searched for cases with PF findings and a postnatal diagnosis of PS. All records were evaluated for ultrasound and MRI findings and the postnatal outcome. PS was diagnosed after birth according to the consensus statement on diagnostic criteria for PS from 2009. The imaging findings of the PS fetuses were compared to a group of consecutive cases with fetal UCH, whose postnatal diagnosis was not PS. Results The PS group included 10 fetuses. All were referred due to UCH accompanied by an ipsilateral retrocerebellar cyst. All pregnancies resulted in livebirths, all newborns had a large segmental facial hemangioma. In all PS fetuses the affected cerebellar hemisphere was upwardly displaced by an ipsilateral PF cyst communicating with an asymmetrically distended 4th ventricle. An upwardly rotated and deviated vermis merged with the contralateral cerebellar peduncles forming an elongated oblique connection between the cerebellar hemispheres, resulting in a unique cerebellar shape, “a tilted telephone receiver sign” (TTRS), on the coronal plane through the upper vermis.The non-PS group included 11 fetuses with UCH: clastic cerebellar lesions (8) and a unilateral PF arachnoid cyst (3). The TTRS was not depicted in any of them (p Conclusions The cerebellar TTRS is a specific fetal imaging feature of PHACES syndrome enabling its prenatal diagnosis.

To construct prenatal age-specific reference intervals for sonographic measurements of the optic nerve sheath diameter (ONSD) during gestation in normal fetuses. Prospective cross-sectional study of fetuses assessed in antenatal ultrasound units between 2010 and 2014. The examination was based on a technique for the sonographic assessment of ONSD previously published by our group. The mean values and SDs of the ONSD were modeled as a function of the gestational week by curve estimation analysis based on the highest adjusted R2 coefficient. Repeatability tests were performed to assess intraobserver variability and interobserver agreement. During the study period 364 healthy fetuses were enrolled. The mean values for the ONSD varied from 0.6 mm at 15-16 weeks to 2.8 mm at 37-38 weeks. The ONSD grows in a linear fashion throughout gestation, with a quadratic equation providing an optimal fit to the data (adjusted R2 = 0.957). Sonographic age-specific references for the fetal ONSD are presented. This data may assist in the decision-making process in fetuses with a suspected increase in intracranial pressure, or anomalies affecting the development of optic stalks, such as optic hypoplasia and septo-optic dysplasia.ZIEL: Bestimmung von pränatalen, altersbezogenen Referenzintervallen für sonografische Messungen des Durchmessers der Sehnervscheide („optic nerve sheath diameter“ = ONSD) bei normalen Feten über die gesamte Schwangerschaft. Prospektive Querschnittsstudie an Feten, die zwischen 2010 und 2014 in Zentren für Pränataldiagnostik beurteilt wurden. Die Untersuchung basierte auf einer zuvor von unserer Gruppe publizierten Methode zur sonografischen Bewertung des ONSD. Die Mittelwerte und SDs des ONSD wurden als Funktion der Schwangerschaftswoche durch Kurvenschätzungsanalyse basierend auf dem höchsten bereinigten R2-Koeffizienten dargestellt. Für die Bewertung der Intraobserver-Variabilität und Interobserver-Übereinstimmung wurden Reproduzierbarkeitsteste durchgeführt. Im Studienzeitraum wurden 364 gesunde Feten aufgenommen. Die Mittelwerte für den ONSD variierten von 0,6 mm in der 15. –16. Woche bis 2,8 mm in der 37. –38. Woche. Der ONSD nimmt während der Schwangerschaft linear zu, wobei eine quadratische Gleichung eine optimale Anpassung an die Daten liefert (bereinigter R2 = 0,957). Es wurden sonografische altersspezifische Referenzwerte für den fetalen ONSD vorgestellt. Diese Daten können bei Feten mit Verdacht auf intrakraniellen Druckanstieg oder bei Anomalien, die die Bildung der Augenstiele beeinträchtigen, wie z. B. optische Hypoplasie und septo-optische Dysplasie, zur Entscheidungsfindung beitragen.

Objectives Fetal aberrant right subclavian artery (ARSA) is a relatively common sonographic finding. Several studies have reported a significant association between ARSA and Down syndrome, as well as 22q11.2 microdeletion. The objective of this study was to assess the risk of abnormal chromosomal microarray analysis (CMA) findings in a large cohort of pregnancies with fetal ARSA as an isolated, as well as a non-isolated, sonographic anomaly. A secondary objective was to review the literature, examining the frequency of chromosomal microarray aberrations in fetuses with isolated ARSA. Methods Data from all pregnancies referred for invasive testing and CMA due to sonographic diagnosis of fetal ARSA, between 2013 and 2017, were obtained retrospectively from the computerized database of the Israeli Ministry of Health. The rate of clinically significant CMA findings in these fetuses was compared to that in a local control population of 2752 low-risk pregnancies with normal ultrasound and serum screening results. In addition, a literature search was conducted in PubMed, from inception to February 2018, of original studies in the English language describing the frequency and nature of microscopic and submicroscopic aberrations in fetuses with isolated ARSA. Results Of 246 pregnancies with isolated ARSA that underwent CMA analysis, a clinically significant finding was detected in one (0.4%) pregnancy (trisomy 21). This rate did not differ significantly from that in the control population (P = 0.1574). Of 22 fetuses with non-isolated ARSA, one (4.5%) additional case of trisomy 21 was noted. The frequency of trisomy 21 in this cohort also did not differ from that in the control population (relative risk, 5.5 (95% CI, 0.8-37.6)). The literature search yielded 13 additional relevant papers, encompassing 333 cases of isolated ARSA. Of 579 cases overall (including those of the present study), 13 (2.2%) cases of trisomy 21 were detected, with no cases of 22q11.2 microdeletion. Conclusion While an association may exist between non-isolated ARSA and Down syndrome, isolated ARSA might better serve as a soft marker for Down syndrome, rather than a routine indication for invasive prenatal testing. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Objectives Periventricular nodular heterotopia (PNH) is a malformation of cortical development which presents with heterogeneous imaging, neurological phenotype and outcome. There is a paucity of comprehensive description detailing the prenatal diagnosis of PNH. The aim of this study is to report neuroimaging features and correlated outcomes in order to delineate the spectrum of prenatally diagnosed PNH. Methods It was a retrospective study over 15 years in five tertiary centers. All fetuses with prenatally diagnosed PNH were collected. Fetal ultrasound and MRI were reviewed and genetic screening collected. Prenatal findings were analyzed in correlation to fetopathological analyses and post-natal follow up. Results Thirty fetuses (22 females and 8 males) with PNH were identified. The two major ultrasound signs were ventriculomegaly associated with dysmorphic frontal horns (60%) and posterior fossa anomalies (73.3%). On MRI, two groups of PNH were identified: the contiguous and diffuse PNH (n = 15, 50%), often associated with megacisterna magna, and the non-diffuse, either anterior, posterior or unilateral PNH. FLNA mutations were found in 6/11 cases with diffuse PNH. Additional cortical malformations were exclusively observed in non diffuse PNH (9/15; 60%). Twenty-four pregnancies (80%) were terminated. Six children aged 6 months to 5 years are alive. Five have normal neurodevelopment (all had diffuse PNH) whereas one case with non diffuse PNH has developmental delay and epilepsy. Conclusion PNH is heterogeneous but patients with diffuse PNH are a common subgroup with specific findings on prenatal imaging and implications for prenatal counseling.

Background ARSACS (autosomal–recessive spastic ataxia of Charlevoix-Saguenay) is a neurodegenerative disorder caused by SACS gene mutations and characterized by a triad of symptoms: early-onset cerebellar ataxia, spasticity and peripheral neuropathy. A characteristic retinal nerve fiber hypertrophy has been reported in several individuals with ARSACS. Methods We describe a patient with a unique clinical presentation of ataxia, nystagmus, dysarthria, hearing impairment, and retinal degeneration. Whole-exome-sequencing was performed as well as morphological studies in the patient's fibroblasts. Results A compound heterozygosity for a novel D3269N and N2380K mutations in the SACS gene was found. The parents are carriers. Morphological studies revealed a dramatic decrease in the number of cell mitochondria as well as a difference in mitochondrial network morphology. Conclusions Retinal degeneration has never been reported in ARSACS. Since sacsin is involved in the mitochondrial fusion-fission process, we speculate that defected fission process may be responsible for an impaired mitochondrial function and retinal degeneration. Our patient has a unique clinical presentation of SACS mutations inconsistent with the classic ARSACS triad but also different from the “atypical” presentations described in the literature. Further studies are necessary to clarify the factors that modify the SACS related phenotype.

Objective Paroxysmal tonic upward gaze was initially described as a benign phenomenon with negative investigations and eventual complete resolution of symptoms. Later publications demonstrated that a similar clinical picture may arise from structural brain lesions, channelopathies, neurotransmitter disorders, and epileptic seizures. CACNA1A related disorders manifest as a wide spectrum of paroxysmal neurological disorders: episodic ataxia 2, hemiplegic migraine, benign paroxysmal torticollis of infancy, and paroxysmal vertigo. Paroxysmal tonic upward gaze as a phenomenon in patients with mutations in the CACNA1A gene has only been reported once. Methods We describe three patients with multiple episodes of paroxysmal tonic upward gaze that appeared during the first months of life. In addition the patients demonstrated motor and language delay and cerebellar ataxia. A sequence analysis of the CACNA1A gene in one patient and whole exome sequencing in the other patients were performed. Results Sequence analysis of the CACNA1A gene in one patient and whole exome sequencing in the two other patients revealed 3 different de-novo mutations in the CACNA1A gene. Conclusion CACNA1A mutations should be evaluated in infants and young children with paroxysmal tonic upgaze especially if associated with developmental delay, cerebellar signs, and other types of paroxysmal event.

SummaryObjective Recently, de novo mutations in GRIN1 have been identified in patients with nonsyndromic intellectual disability and epileptic encephalopathy. Whole exome sequencing (WES) analysis of patients with genetically unsolved epileptic encephalopathies identified four patients with GRIN1 mutations, allowing us to investigate the phenotypic spectrum of GRIN1 mutations. Methods Eighty-eight patients with unclassified early onset epileptic encephalopathies (EOEEs) with an age of onset A) with a mutant allele frequency of 16% (in DNA of blood leukocytes) was detected in one patient. Three mutations were located in the transmembrane domain (3/4, 75%), and one in the extracellular loop near transmembrane helix 1. All the mutations were predicted to impair the function of the NMDA receptor. Significance Clinical features of de novo GRIN1 mutations include infantile involuntary movements, seizures, and hand stereotypies, suggesting that GRIN1 mutations cause encephalopathy resulting in seizures and movement disorders.

Costeff syndrome is a rare genetic neuro-ophthalmological syndrome consisting of early-onset bilateral optic atrophy along with a progressive complex motor disorder with elevated levels of urinary 3-methylglutaconic acid and 3-methylglutaric acid. While borderline to mild cognitive deficits have been considered to be common in patients with this syndrome, a comprehensive cognitive assessment has never been performed. The aim of the current study was to explore the cognitive profile associated with Costeff syndrome. Sixteen adult patients diagnosed with Costeff syndrome were administered a neuropsychological test battery that was composed of standardized verbal tests adapted for the blind. General intelligence ranged from average to borderline, with a group mean consistent with intact general cognitive functioning (VIQmean = 85, z = -1) in the low-average range of the general population. The auditory immediate and delayed memory indexes were in the average range and were significantly higher than the general cognitive functioning, whereas the working memory index was significantly lower than the general cognitive functioning. Adult patients with Costeff syndrome have intact global cognition and learning abilities and strong auditory memory performance. © 2015 Wiley Periodicals, Inc.

Objective To examine the risk for clinically significant chromosomal microarray analysis (CMA) among fetuses with apparently isolated horseshoe kidney. Methods Data from all CMA analyses performed due to isolated horseshoe kidney reported to the Israeli Ministry of Health between January 2013 and September 2016 were retrospectively obtained from a computerized database. Risk estimation was performed comparing the rate of abnormal CMA findings to the general population, based on a systematic review encompassing 9272 pregnancies with normal ultrasound, and local data cohort of 5541 pregnancies undergoing CMA due to maternal request. Results Of 82 pregnancies with isolated horseshoe kidney, one loss-of-copy-number variant compatible with 16p13.11 microdeletion syndrome was demonstrated (1.2%). In addition, two variants of unknown significance (VOUS) were detected (2.4%). The relative risk for pathogenic CMA findings among pregnancies with isolated single horseshoe kidney was not significantly different from the control population (1.03–1.39%). Discussion To our best knowledge, our study is the first report describing the rate of clinically significant CMA findings in fetuses with isolated horseshoe kidney. The detection of one pathogenic CMA findings in our cohort implies that the value of CMA analysis in such pregnancies is similar to the general population.

Glutaminyl tRNA synthase is highly expressed in the developing fetal human brain. Mutations in the glutaminyl-tRNA synthetase (QARS) gene have been reported in patients with progressive microcephaly, cerebral-cerebellar atrophy, and intractable seizures. We have previously reported a new recessive syndrome of severe linear growth retardation, poor weight gain, microcephaly, characteristic facial features, cutaneous syndactyly of the toes, high myopia, and intellectual disability in two sisters of Ashkenazi-Jewish origin (Eur J Med Genet 2014;57(6):288-92). Homozygosity mapping and whole exome sequencing revealed a homozygous missense (V476I) mutation in the QARS gene, located in the catalytic domain. The patient's fibroblasts demonstrated markedly reduced QARS amino acylation activity in vitro. Furthermore, the same homozygous mutation was found in an unrelated girl of Ashkenazi origin with the same phenotype. The clinical presentation of our patients differs from the original QARS-associated syndrome in the severe postnatal growth failure, absence of epilepsy, and minor MRI findings, thus further expanding the phenotypic spectrum of the glutaminyl-tRNA synthetase deficiency syndromes.

Aicardi-Goutières syndrome is a genetic neurodegenerative disorder with clinical symptoms mimicking a congenital viral infection. Mutations in 6 genes are known to cause the disease: 3 prime repair exonuclease1, ribonucleases H2A, B, and C, SAM domain and HD domain 1, and most recently ADAR1. HD domain 1 mutations were previously reported in the Ashkenazi-Jewish community. We report an additional patient of Ashkenazi-Jewish descent and review the other 3 cases affected with Aicardi-Goutières syndrome due to SAM domain and HD domain 1 ( SAMHD1) mutations described in Israel. We propose that there may be a phenotypic-genotypic correlation in accordance with the type of mutations inherited in the SAMHD1 genotype and suggest that Aicardi-Goutières syndrome may not be a rare disease in the Ashkenazi-Jewish population.

Costeff syndrome (CS) is a rare autosomal-recessive neurological disorder, which is known almost exclusively in patients of Iraqi Jewish descent, manifesting in childhood with optic atrophy, ataxia, chorea and spastic paraparesis. Our aim was to study the clinical spectrum of CS and natural history using a cross-sectional study design. Consecutive patients with CS were recruited to the study. Patients were diagnosed based on clinical features, along with elevated urinary levels of methylglutaconic and methylglutaric acid, and by identification of the disease-causing mutation in the OPA3 gene in most. All patients were examined by a neurologist and signs and symptoms were rated. 28 patients with CS (16 males, 21 families, age at last observation 28.6 ± 16.1 years, range 0.5-68 years) were included. First signs of neurological deficit appeared in infancy or early childhood, with delayed motor milestones, choreiform movements, ataxia and visual disturbances. Ataxia and chorea were the dominant motor features in childhood, but varied in severity among patients and did not seem to worsen with age. Pyramidal dysfunction appeared later and progressed with age (r = 0.71, p < 0.001) leading to spastic paraparesis and marked gait impairment. The course of neurological deterioration was slow and the majority of patients could still walk beyond the fifth decade. While visual acuity seemed to deteriorate, it did not correlate with age. CS is a rare neurogenetic disorder that causes serious disability and worsens with age. Spasticity significantly increases over the years and is the most crucial determinant of neurological dysfunction.

Ohtahara syndrome is a devastating early infantile epileptic encephalopathy caused by mutations in different genes. We describe a patient with Ohtahara syndrome who presented on the first day of life with refractory tonic seizures and a suppression-burst pattern on EEG. The patient developed severe microcephaly, and never achieved any developmental milestones. He died at the age of 5 years. A de novo missense mutation (c. 4007C>A, p.S1336Y) in SCN2A was found. Interestingly, the father has another son with Ohtahara syndrome from a different mother. The half brother carries the same SCN2A mutation, strongly suggesting paternal gonadal mosaicism of the mutation. The broad clinical spectrum of SCN2A mutations now includes Ohtahara syndrome. This is the first report of familial Ohtahara syndrome due to a germline mosaic SCN2A mutation. Somatic mosaicism, including germline, has been described in several epileptic encephalopathies such as Dravet syndrome, KCNQ2 neonatal epileptic encephalopathy, SCN8A epileptic encephalopathy and STXBP1 related Ohtahara syndrome. Mosaicism should be considered as one of the important inheritance patterns when counseling parents with a child with these devastating diseases.

Objective To examine the long-term neuropsychological outcome of children with a prenatal diagnosis of asymmetric ventricles or unilateral ventriculomegaly. Design A clinic-based neuropsychological study. Setting Paediatric neurology clinic. Population Thirty-three of 41 children, previously assessed at kindergarten age, with asymmetric ventricles or unilateral ventriculomegaly identified in utero, were recruited at school age for a neuropsychological follow-up. Methods All children, 9–11 years of age, underwent a battery of neuropsychological tests and the parents completed behavioural rating questionnaires. Main outcome measures Results of the neuropsychological assessment and parents' questionnaires. Results There were no significant differences between children diagnosed with either asymmetric ventricles or unilateral ventriculomegaly in most parameters relative to the general population; the full-scale IQ scores were 103.13 ± 12.43 and 103.56 ± 10.5, respectively. A significantly lower performance was found only on one measure of attention among the unilateral ventriculomegaly group and on writing speed tasks among the asymmetric ventricles group. Both study groups showed significantly higher scores than expected in the normal population on a verbal fluency test. Comparison of both groups combined with the normative population yielded significantly lower scores only in attention tests. Yet, the clinical population showed significantly higher scores on writing accuracy, processing speed and verbal fluency and lower rates of executive dysfunction. Conclusions Asymmetric ventricles or unilateral ventriculomegaly identified in utero does not appear to affect long-term mental development and school achievements. Further prospective research on a larger sample is needed in order to confirm our findings.

Introduction There are many similarities, both clinical and radiological, between mitochondrial leukoencephalopathies and Alexander disease, an astrogliopathy. Clinically, both can manifest with a myriad of symptoms and signs, arising from the neonatal period to adulthood. Radiologically, both can demonstrate white matter changes, signal abnormalities of basal ganglia or thalami, brainstem abnormalities and contrast enhancement of white matter structures. Magnetic resonance spectroscopy may reveal elevation of lactate in the abnormal white matter in Alexander disease making the distinction even more challenging. Patient and Methods We present a child who was considered to have an infantile onset mitochondrial disorder due to a combination of neurological symptoms and signs (developmental regression, failure to thrive, episodic deterioration, abnormal eye movements, pyramidal and cerebellar signs), urinary excretion of 3-methyl-glutaconic acid and imaging findings (extensive white matter changes and cerebellar atrophy) with a normal head circumference. Whole exome sequence analysis was performed. Results The child was found to harbor the R416W mutation, one of the most prevalent mutations in the glial fibrillary acidic protein (GFAP) gene that causes Alexander disease. Conclusions Alexander disease should be considered in the differential diagnosis of infantile leukoencephalopathy, even when no macrocephaly is present. Next generation sequencing is a useful aid in unraveling the molecular etiology of leukoencephalopathies.

Genetic syndromes with proportionate severe short stature are rare. We describe two sisters born to nonconsanguineous parents with severe linear growth retardation, poor weight gain, microcephaly, characteristic facial features, cutaneous syndactyly of the toes, high myopia, and severe intellectual disability. During infancy and early childhood, the girls had transient hepatosplenomegaly and low blood cholesterol levels that normalized later. A thorough evaluation including metabolic studies, radiological, and genetic investigations were all normal. Cholesterol metabolism and transport were studied and no definitive abnormality was found. No clinical deterioration was observed and no metabolic crises were reported. After due consideration of other known hereditary causes of post-natal severe linear growth retardation, microcephaly, and intellectual disability, we propose that this condition represents a newly recognized autosomal recessive multiple congenital anomaly-intellectual disability syndrome.

Background Progressive cerebello-cerebral atrophy (PCCA) leading to profound mental retardation, progressive microcephaly, spasticity and early onset epilepsy, was diagnosed in four non-consanguineous apparently unrelated families of Jewish Moroccan ancestry. Common founder mutation(s) were assumed. Methods Genome-wide linkage analysis and whole exome sequencing were done, followed by realtime PCR and immunofluorescent microscopy. Results Genome-wide linkage analysis mapped the disease-associated gene to 0.5 Mb on chromosome 17p13.3. Whole exome sequencing identified only two mutations within this locus, which were common to the affected individuals: compound heterozygous mutations in VPS53 , segregating as expected for autosomal recessive heredity within all four families, and common in Moroccan Jews (∼1:37 carrier rate). The Golgi-associated retrograde protein (GARP) complex is involved in the retrograde pathway recycling endocytic vesicles to Golgi; c.2084A>G and c.1556+5G>A VPS53 founder mutations are predicted to affect the C-terminal domain of VPS53, known to be critical to its role as part of this complex. Immunofluorescent microscopy demonstrated swollen and abnormally numerous CD63 positive vesicular bodies, likely intermediate recycling/late endosomes, in fibroblasts of affected individuals. Conclusions Autosomal recessive PCCA type 2 is caused by VPS53 mutations.

ObjectiveTo provide new insights into theFOXG1-related clinical and imaging phenotypes and refine the phenotype-genotype correlation inFOXG1syndrome.MethodsWe analyzed the clinical and imaging phenotypes of a cohort of 45 patients with a pathogenic or likely pathogenicFOXG1variant and performed phenotype-genotype correlations.ResultsA total of 37FOXG1different heterozygous mutations were identified, of which 18 are novel. We described a broad spectrum of neurodevelopmental phenotypes, characterized by severe postnatal microcephaly and developmental delay accompanied by a hyperkinetic movement disorder, stereotypes and sleep disorders, and epileptic seizures. Our data highlighted 3 patterns of gyration, including frontal pachygyria in younger patients (26.7%), moderate simplified gyration (24.4%) and mildly simplified or normal gyration (48.9%), corpus callosum hypogenesis mostly in its frontal part, combined with moderate-to-severe myelination delay that improved and normalized with age. Frameshift and nonsense mutations in the N-terminus ofFOXG1, which are the most common mutation types, show the most severe clinical features and MRI anomalies. However, patients with recurrent frameshift mutations c.460dupG and c.256dupC had variable clinical and imaging presentations.ConclusionsThese findings have implications for genetic counseling, providing evidence that N-terminal mutations and large deletions lead to more severeFOXG1syndrome, although genotype-phenotype correlations are not necessarily straightforward in recurrent mutations. Together, these analyses support the view thatFOXG1syndrome is a specific disorder characterized by frontal pachygyria and delayed myelination in its most severe form and hypogenetic corpus callosum in its milder form.