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Objective: To study prenatal diagnosis of congenital Treacher Collins syndrome, an etiology of craniofacial abnormalities. Case report: We present a case of fetal craniofacial abnormalities identified by antepartum sonography screening in the third trimester (28 weeks); features of micrognathia, hypoplastic zygomatic arches and bilateral low-set microtia were detected. Due to the unknown severity of the craniofacial abnormalities and poor prognosis, the parents decided to terminate the fetus after through counselling. A normal female karyotype was detected. The parents consented to chromosome microarray analysis (CMA), which identified a de novo mutation of the TCS1 gene locus on chromosome 5. Conclusion: Molecular CMA is an effective tool for prenatal diagnosis of congenital craniofacial abnormalities associated with Treacher Collins syndrome.

Introduction: Intellectual disorders involving deletions of the X chromosome present a difficult task in the determination of a connection between symptoms and metabolites that could lead to treatment options. One specific disorder of X-chromosomal deletion, Fragile X syndrome, is the most frequently occurring of intellectual disabilities. Previous metabolomic studies have been limited to mouse models that may not have sufficiently revealed the full biochemical diversity of the disease in humans. Objectives: The primary objective of this study was to elucidate the human biochemistry in X-chromosomal deletion disorders through metabolomic and lipidomic profiling, using cells from a X-deletion patient as a representative case. Methods: Metabolomic and lipidomic analysis was performed by UHPLC-HRMS on neural progenitor (NP) cells isolated from an afflicted female patient versus normal neural progenitor cells. Results: Results showed perturbations in several metabolic pathways, including those of arginine and proline, that significantly impact both neurotransmitter generation and overall brain function. Coincidently, dysregulation was observed for lipids involved in both cellular structure and membrane integrity. The trends of observed metabolomic changes, as well as lipidomic profiling from identified features, are discussed. Conclusion: The lipidomic and metabolomic profiles of NP cell samples exhibited significant differentiation associated with partial deletion of the X chromosome. These findings suggest that rare X-chromosomal deletion disorders are not only a mental disorder limited to alterations in local neuronal functions, but are also metabolic diseases.

Objective: The objective of this study was to report the first case of prenatal diagnosis of the fetal 20p13 microdeletion syndrome in the literature. Case report: The mother was 31 years old and had a first trimester serum screening that indicated the fetus was at low risk. The prenatal ultrasound at 23 weeks of gestation showed mild ventriculomegaly (10.2 mm) and absent septum pellucidum. She underwent amniocentesis because of the abnormal imaging results. Karyotype analysis revealed normal results. Chromosome microarray analysis (CMA) was then performed to provide genetic analysis of the fetus and parents. CMA detected 317.902 kb deletion of 20p13 in fetus. Finally, pregnancy was terminated at 32 weeks of gestation. Conclusion: This study is the first to report the prenatal diagnosis of a 20p13 microdeletion syndrome. Our results further confirmed that genes in this region, including SOX12, NRSN2 are essential for normal fetal growth and TBC1D20 for normal brain development.

Background: Citrullinemia type I (CTLN1, MIM #215700) is an autosomal recessive urea cycle disorder caused by deficiency of argininosuccinate synthase (ASS). CTLN1 is characterized by life-threatening hyperammonemia and risk for resulting neurocognitive impairments. The diagnosis of CTLN1 is confirmed by the identification of biallelic pathogenic variants in the ASS1 gene. However, there are a small percentage of CTLN1 patients with a characteristic biochemical phenotype without identifiable variants in ASS1. We describe the molecular characterization of two related Romani children with biochemically diagnosed CTLN1, whose clinical genetic testing failed to detect any pathogenic variant in ASS1. Methods: Genomic DNA was extracted from peripheral blood lymphocytes collected from both patients. Sanger sequencing was performed after PCR amplifications of 5′- and 3′-untranslated regions of the ASS1 gene. A luciferase reporter assay was performed using the human malignant melanoma A2058 cell line and the human liver cancer cell line HepG2. Results: We interrogated the non-coding regions of ASS1 by targeted PCR amplification and identified a homozygous 477-bp microdeletion in the promoter region of the ASS1 gene in both patients. Heterozygosity of the variant was confirmed in their parents. Sanger sequencing confirmed the microdeletion contained the entire sequence of the non-coding exon 1 of ASS1 that includes promoter elements of GC-box, E-box, AP2-binding site, and TATA-box. Luciferase reporter assay using an expression plasmid containing the wild-type or mutant ASS1 sequences showed robust reporter expression from the wild-type sequence and significantly reduced expression driven by the mutant insert (3.6% in A2058 cells and 3.3% in HepG2 cells). These findings were consistent with the hypothesis that the microdeletion identified in the patients disrupted an essential promoter element and resulted in deficiency of ASS1 mRNA expression. Conclusions: This is the first report of CTLN1 patients caused by a Romani microdeletion variant affecting the non-coding upstream sequence of ASS1. Ablation of the promoter sequence can cause CTLN1 by the reduction of ASS1 expression. Currently available clinical sequencing methods usually do not cover the promoter sequence including the non-coding exon of ASS1, highlighting the importance of evaluating this region in genetic testing for CTLN1.

We report the first microdeletion (26 kb) of the biotinidase gene (BTD) that involves three of the four exons of the gene. This deletion further exemplifies the importance of performing microarray analysis or other methodologies for a deletion of the BTD gene when the enzymatic activity indicates lower activity than can be attributed to the mutations identified by DNA sequencing.

Gephyrin is a postsynaptic scaffolding protein, essential for the clustering of glycine and γ-aminobutyric acid type-A receptors (GABAARs) at inhibitory synapses. An impairment of GABAergic synaptic inhibition represents a key pathway of epileptogenesis. Recently, exonic microdeletions in the gephyrin (GPHN) gene have been associated with neurodevelopmental disorders including autism spectrum disorder, schizophrenia and epileptic seizures. Here we report the identification of novel exonic GPHN microdeletions in two patients with idiopathic generalized epilepsy (IGE), representing the most common group of genetically determined epilepsies. The identified GPHN microdeletions involve exons 5–9 (Δ5–9) and 2–3 (Δ2–3), both affecting the gephyrin G-domain. Molecular characterization of the GPHN Δ5–9 variant demonstrated that it perturbs the clustering of regular gephyrin at inhibitory synapses in cultured mouse hippocampal neurons in a dominant-negative manner, resulting in a significant loss of γ2-subunit containing GABAARs. GPHN Δ2–3 causes a frameshift resulting in a premature stop codon (p.V22Gfs*7) leading to haplo-insufficiency of the gene. Our results demonstrate that structural exonic microdeletions affecting the GPHN gene constitute a rare genetic risk factor for IGE and other neuropsychiatric disorders by an impairment of the GABAergic inhibitory synaptic transmission.

Episodic falling syndrome (EFS) is a canine paroxysmal hypertonicity disorder found in Cavalier King Charles spaniels. Episodes are triggered by exercise, stress or excitement and characterized by progressive hypertonicity throughout the thoracic and pelvic limbs, resulting in a characteristic 'deer-stalking' position and/or collapse. We used a genome-wide association strategy to map the EFS locus to a 3.48 Mb critical interval on canine chromosome 7. By prioritizing candidate genes on the basis of biological plausibility, we found that a 15.7 kb deletion in BCAN, encoding the brain-specific extracellular matrix proteoglycan brevican, is associated with EFS. This represents a compelling causal mutation for EFS, since brevican has an essential role in the formation of perineuronal nets governing synapse stability and nerve conduction velocity. Mapping of the deletion breakpoint enabled the development of Multiplex PCR and Multiplex Ligation-dependent Probe Amplification (MLPA) genotyping tests that can accurately distinguish normal, carrier and affected animals. Wider testing of a larger population of CKCS dogs without a history of EFS from the USA revealed that carriers are extremely common (12.9%). The development of molecular genetic tests for the EFS microdeletion will allow the implementation of directed breeding programs aimed at minimizing the number of animals with EFS and enable confirmatory diagnosis and pharmacotherapy of affected dogs.

We report on a female individual with feeding difficulties, constipation, poor overall growth, periventricular lesions resembling gliosis in brain MRI, recurrent otitis media with palsy of facial nerve, distinct facial features, and pronounced delay in speech development. The latter was the most prominent feature. Molecular karyotyping revealed a heterozygous de novo deletion of 4.353 Mb at chromosome 12q21.33q22. This report expands the number of described individuals with heterozygous deletions at 12q21.33, their clinical spectrum and highlights the clinical variability, even in individuals with deletion of the same genes. Furthermore, our findings indicate a role of BTG1 (OMIM *109580) in speech development., Competing Interests: Declaration of competing interest The authors declare to have no conflicts of interest., (Copyright © 2023 Elsevier Masson SAS. All rights reserved.)

Hereditary pancreatic cancer has been attributed to variants of several cancer predisposition genes including ATM. While heterozygous pathogenic variants in the ATM gene are implicated as a cause of familial breast and pancreatic cancers to our knowledge ATM whole gene deletions have not been previously reported. We describe a contiguous gene deletion of the ATM locus in a multi-generation family of Italian descent with a strong family history of pancreatic cancer. A deletion of one copy of the entire ATM gene was identified by routine panel testing and further characterized by chromosomal microarray analysis. An 11q22.3 microdeletion of approximately 960 kb was identified that is predicted to result in loss of 10 genes including ATM. The deletion was identified in two additional family members including a presymptomatic daughter and an affected sibling. A normal disomic complement of the 11q22.3 region was detected in a third family member with a history of prostate and pancreatic cancer. Additional family members were not available for testing. Given available evidence that ATM haploinsufficiency can increase cancer risk, we predict that the observed copy number loss has likely contributed to hereditary cancer in this family. However, absence of the familial microdeletion in at least one affected family member suggests that ATM deletions are unlikely the sole contributing factor influencing tumor development in affected individuals. This case highlights 11q22.3 microdeletions of the ATM gene region as a possible risk factor for hereditary cancer, including pancreatic cancer. The same case provides a further cautionary tale for over interpretation of cancer risk associated tumor suppressor microdeletions and suggests that the variant may not be sufficient for tumor development or may modify the cancer risks associated with other, yet unidentified hereditary cancer genes., (Copyright © 2019. Published by Elsevier Inc.)

Background: Microdeletions and microduplications can occur in any pregnancy independent of maternal age. The spectrum and features of pathogenic copy number variants including the size, genomic distribution, and mode of inheritance are not well studied. These characteristics have important clinical implications regarding expanding noninvasive prenatal screening for microdeletions and microduplications., Objectives: The aim was to investigate the spectrum and characteristics of pathogenic copy number variants in prenatal genetic diagnosis and to provide recommendations for expanding the scope of noninvasive prenatal screening for microdeletions and microduplications., Study Design: This was a retrospective study of 1510 pregnant women who underwent invasive prenatal diagnostic testing by chromosomal microarray analysis. Prenatal samples were retrieved by amniocentesis or chorionic villus sampling and sent to our prenatal genetic diagnosis laboratory for chromosomal microarray analysis. The risk of carrying a fetus with pathogenic copy number variants is stratified by the patients' primary indication for invasive testing. We searched the literature for published prenatal chromosomal microarray data to generate a large cohort of 23,865 fetuses. The characteristics and spectrum of pathogenic copy number variants including the type of aberrations (gains or losses), genomic loci, sizes, and the mode of inheritance were studied., Results: Overall, 375 of 23,865 fetuses (1.6%) carried pathogenic copy number variants for any indication for invasive testing, and 44 of them (11.7%) involve 2 or more pathogenic copy number variants. A total of 428 pathogenic copy number variants were detected in these fetuses, of which 280 were deletions and 148 were duplications. Three hundred sixty (84.1%) were less than 5 Mb in size and 68 (15.9%) were between 5 and 10 Mb. The incidence of carrying a pathogenic copy number variant in the high-risk group is 1 in 36 and the low-risk group is 1 in 125. Parental inheritance study results were available for 311 pathogenic copy number variants, 71 (22.8%) were maternally inherited, 36 (11.6%) were paternally inherited, and 204 (65.6%) occurred de novo., Conclusion: Collectively, pathogenic copy number variants are common in pregnancies. High-risk pregnancies should be offered invasive testing with chromosomal microarray analysis for the most comprehensive investigation. Detection limits on size, parental inheritance, and genomic distribution should be carefully considered before implementing copy number variant screening in expanded noninvasive prenatal screening., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Noninvasive prenatal testing for fetal aneuploidy using cell-free DNA has been widely integrated into routine obstetrical care. The scope of cell-free DNA testing has expanded from trisomies 21, 18, and 13 to include sex chromosome conditions, panels of specific microdeletions, and more recently genome-wide copy number variants and rare autosomal trisomies. Because the technical ability to test for a condition does not necessarily correspond with a clinical benefit to a population or to individual pregnant women, the benefits and harms of screening programs must be carefully weighed before implementation. Application of the World Health Organization criteria to cell-free DNA screening is informative when considering implementation of expanded cell-free DNA test menus. Most microdeletions and duplications are rare to the point that the prevalence has not even been defined and their natural history cannot be reliably predicted in the prenatal period. At the current time, scientific evidence regarding clinical performance of expanded cell-free DNA panels is lacking. Expanded cell-free DNA menus therefore create a dilemma for diagnosis, treatment, and counseling of patients. The clinical utility of expanding cell-free DNA testing to include panels of microdeletions and genome-wide assessment of large chromosomal imbalances has yet to be demonstrated; as such, the clinical implementation of this testing is premature., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Purpose: Contiguous gene deletions are known to cause several neurodevelopmental syndromes, many of which are caused by recurrent events on chromosome 16. However, chromosomal microarray studies (CMA) still yield copy-number variants (CNVs) of unknown clinical significance. We sought to characterize eight individuals with overlapping 205-kb to 504-kb 16p13.3 microdeletions that are distinct from previously published deletion syndromes., Methods: Clinical information on the patients and bioinformatic scores for the deleted genes were analyzed., Results: All individuals in our cohort displayed developmental delay, intellectual disability, and various forms of seizures. Six individuals were microcephalic and two had strabismus. The deletion was absent in all 13 parents who were available for testing. The area of overlap encompasses seven genes including TBC1D24, ATP6V0C, and PDPK1 (also known as PDK1). Bi-allelic TBC1D24 pathogenic variants are known to cause nonsyndromic deafness, epileptic disorders, or DOORS syndrome (deafness, onychodystrophy, osteodystrophy, mental retardation, seizures). Sanger sequencing of the nondeleted TBC1D24 allele did not yield any additional pathogenic variants., Conclusions: We propose that 16p13.3 microdeletions resulting in simultaneous haploinsufficiencies of TBC1D24, ATP6V0C, and PDPK1 cause a novel rare contiguous gene deletion syndrome of microcephaly, developmental delay, intellectual disability, and epilepsy.

Proper function of GABAergic synapses depends upon the postsynaptic compartment anchoring of neurotransmitter receptors to the membrane by gephyrin and collybistin (Cb). In humans, Cb is encoded by ARHGEF9 on Xq11.1. ARHGEF9 alterations, some inherited from unaffected mothers, have been reported in males with autism, seizures and severe neurodevelopmental abnormalities. In females, a spectrum of mild to moderate phenotype has been detected. We report two unrelated females with autism and mild intellectual disability. High resolution X-chromosome microarray analysis revealed de novo intragenic deletions in ARHGEF9 of 24 kb and 56 kb involving exons 5-8 and exons 3-8 and leading to truncated forms of collybistin. Peripheral blood samples revealed random X-chromosome inactivation in both patients. To explain phenotypic variability in female patients, we propose a model for disruption of collybistin and various irregular interactions in post-synaptic neurons based on X inactivation patterns. Our findings highlight the importance of ARHGEF9 integrity and suggest further research on its correlation with autism and neurobehavioral problems., (Copyright © 2018. Published by Elsevier Masson SAS.)

Array-based comparative genomic hybridization is a routine technology that helps clinicians in the diagnostic evaluation of individuals presenting with developmental delay or malformation anomalies. With this technique, several patients affected by microdeletion 2p15-p16.1 have been reported and this anomaly has been recognized as a distinct syndrome. In contrast, clinical features of patients with microduplication in the same region have been registered mainly in clinical and genetic data-bases and to date just a single patient has been reported in detail in the literature. A 12-year-old boy with 2p15-p16.1 microduplication presented with moderate neurodevelopment delay, epileptic seizures, behavioral disturbances, and minor dysmorphic features. The role of 2p15-p16.1 duplication in this case, and the others published in data-bases with a similar molecular duplication, are discussed., (Copyright © 2018. Published by Elsevier Masson SAS.)

Microdeletions at 11q13.1 are very rare. At present only two patients with 11q13.1 deletion involving neurexin 2 (NRXN2) have been reported. Both patients exhibited autistic features, which supported the role of NRXN2 in autism pathogenicity. It is currently unknown whether heterozygous deletion of NRXN2 is of high penetrance or if it is sufficient to result in autism behaviors. Here we reported a 2-year-9-month old boy with developmental delay, short stature, significant language delay and other congenital anomalies. In contrast to previously reported cases, the boy did not present with autistic behaviors and did not meet the clinical diagnosis of autism. A de novo 921 kb microdeletion at 11q13.1 was detected by chromosomal microarray analysis (CMA). Whole Exome Sequencing (WES) was also employed for our patient. The deletion was confirmed and no additional pathogenic variants were detected. We compared our patient's genomic information and clinical features with those of two previously reported individuals. Three patients shared similar deleted intervals and had similar clinical features except for autistic behaviors. This study suggested that NRXN2 gene had incomplete penetrance for autistic behavioral phenotype. The finding is of interest for genetic counseling and clinical management to patients with NRXN2 defects., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Background: Williams-Beuren syndrome (WBS) is caused by a microdeletion of chromosome arm 7q11.23. A rapid and inexpensive genotyping method to detect microdeletion on 7q11.23 needs to be developed for the diagnosis of WBS. This study describes the development of a new type of molecular diagnosis method to detect microdeletion on 7q11.23 based upon high-resolution melting (HRM)., Methods: Four genes on 7q11.23 were selected as the target genes for the deletion genotyping. dNTP-limited duplex PCR was used to amplify the reference gene, CFTR, and one of the four genes respectively on 7q11.23. An HRM assay was performed on the PCR products, and the height ratio of the negative derivative peaks between the target gene and reference gene was employed to analyze the copy number variation of the target region., Results: A new genotyping method for detecting 7q11.23 deletion was developed based upon dNTP-limited PCR and HRM, which cost only 96 min. Samples from 15 WBS patients and 12 healthy individuals were genotyped by this method in a blinded fashion, and the sensitivity and specificity was 100% (95% CI, 0.80-1, and 95% CI, 0.75-1, respectively) which was proved by CytoScan HD array., Significance: The HRM assay we developed is an rapid, inexpensive, and highly accurate method for genotyping 7q11.23 deletion. It is potentially useful in the clinical diagnosis of WBS., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: Currently, chromosomal microarray analysis is considered the first-tier test in pediatric care and prenatal diagnosis. However, the diagnostic yield of chromosomal microarray analysis for prenatal diagnosis of congenital heart disease has not been evaluated based on a large cohort., Objective: Our aim was to evaluate the clinical utility of chromosomal microarray as the first-tier test for chromosomal abnormalities in fetuses with congenital heart disease., Study Design: In this prospective study, 602 prenatal cases of congenital heart disease were investigated using single nucleotide polymorphism array over a 5-year period., Results: Overall, pathogenic chromosomal abnormalities were identified in 125 (20.8%) of 602 prenatal cases of congenital heart disease, with 52.0% of them being numerical chromosomal abnormalities. The detection rates of likely pathogenic copy number variations and variants of uncertain significance were 1.3% and 6.0%, respectively. The detection rate of pathogenic chromosomal abnormalities in congenital heart disease plus additional structural anomalies (48.9% vs 14.3%, P < .0001) or intrauterine growth retardation group (50.0% vs 14.3%, P = .044) was significantly higher than that in isolated congenital heart disease group. Additionally, the detection rate in congenital heart disease with additional structural anomalies group was significantly higher than that in congenital heart disease with soft markers group (48.9% vs 19.8%, P < .0001). No significant difference was observed in the detection rates between congenital heart disease with additional structural anomalies and congenital heart disease with intrauterine growth retardation groups (48.9% vs 50.0%), congenital heart disease with soft markers and congenital heart disease with intrauterine growth retardation groups (19.8% vs 50.0%), or congenital heart disease with soft markers and isolated congenital heart disease groups (19.8% vs 14.3%). The detection rate in fetuses with congenital heart disease plus mild ventriculomegaly was significantly higher than in those with other types of soft markers (50.0% vs 15.6%, P < .05)., Conclusion: Our study suggests chromosomal microarray analysis is a reliable and high-resolution technology and should be used as the first-tier test for prenatal diagnosis of congenital heart disease in clinical practice., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Since its commercial release in 2011 cell-free DNA screening has been rapidly adopted as a routine prenatal genetic test. However, little is known about its performance in actual clinical practice., Objective: We sought to investigate factors associated with the accuracy of abnormal autosomal cell-free DNA results., Study Design: We conducted a retrospective cohort study of 121 patients with abnormal cell-free DNA results from a referral maternal-fetal medicine practice from March 2013 through July 2015. Patients were included if cell-free DNA results for trisomy 21, trisomy 18, trisomy 13, or microdeletions (if reported by the laboratory) were positive or nonreportable. The primary outcome was confirmed aneuploidy or microarray abnormality on either prenatal or postnatal karyotype or microarray. Secondary outcomes were identifiable associations with in vitro fertilization, twins, ultrasound findings, testing platform, and testing laboratory. Kruskal-Wallis or Fisher exact tests were used as appropriate., Results: A total of 121 patients had abnormal cell-free DNA results for trisomy 21, trisomy 18, trisomy 13, and/or microdeletions. In all, 105 patients had abnormal cell-free DNA results for trisomy 21, trisomy 18, and trisomy 13. Of these, 92 (87.6%) were positive and 13 (12.4%) were nonreportable. The results of the 92 positive cell-free DNA were for trisomy 21 (48, 52.2%), trisomy 18 (22, 23.9%), trisomy 13 (17, 18.5%), triploidy (2, 2.2%), and positive for >1 parameter (3, 3.3%). Overall, the positive predictive value of cell-free DNA was 73.5% (61/83; 95% confidence interval, 63-82%) for all trisomies (by chromosome: trisomy 21, 83.0% [39/47; 95% confidence interval, 69-92%], trisomy 18, 65.0% [13/20; 95% confidence interval, 41-84%], and trisomy 13, 43.8% [7/16; 95% confidence interval, 21-70%]). Abnormal cell-free DNA results were associated with positive serum screening (by group: trisomy 21 [17/48, 70.8%]; trisomy 18 [7/22, 77.8%]; trisomy 13 [3/17, 37.5%]; nonreportable [2/13, 16.7%]; P = .004), and abnormal first-trimester ultrasound (trisomy 21 [25/45, 55.6%]; trisomy 18 [13/20, 65%]; trisomy 13 [6/14, 42.9%]; nonreportable [1/13, 7.7%]; P = .003). There was no association between false-positive rates and testing platform, but there was a difference between the 4 laboratories (P = .018). In all, 26 patients had positive (n = 9) or nonreportable (n = 17) microdeletion results. Seven of 9 screens positive for microdeletions underwent confirmatory testing; all were false positives., Conclusion: The positive predictive value of 73.5% for cell-free DNA screening for autosomal aneuploidy is lower than reported. The positive predictive value for microdeletion testing was 0%. Diagnostic testing is needed to confirm abnormal cell-free DNA results for aneuploidy and microdeletions., (Copyright © 2016 Elsevier Inc. All rights reserved.)

In 2012 a small terminal deletion in the short arm of chromosome 10 in the region 10p15.3 was reported as a novel microdeletion syndrome. By now 21 patients, including a single familial case, have been reported. Characteristic findings comprise variable cognitive impairment or developmental delay, disorder of speech development, as well as various dysmorphic signs. We here report on a new patient, an eight year old girl, with a microdeletion syndrome 10p15.3. She is a foster child showing intellectual deficits, disorder of speech development, behavioral problems, congenital heart defect, and several dysmorphic signs. The same microdeletion was subsequently found in the six year old maternal half-sister, showing very similar developmental and cognitive issues, including major speech impairment. The mother has not obtained a school degree. She was described as being a dissocial person with severe alcohol abuse and showing minor cognitive disability. Thus inheritance of the microdeletion from a probably symptomatic mother can be assumed. The patients presented here add up to the as yet small number of reported cases of microdeletion 10p15.3 and thereby might help to establish a more comprehensive clinical spectrum of this rather newly discovered syndrome., (Copyright © 2016 Elsevier Masson SAS. All rights reserved.)

The 3q13.31 microdeletion syndrome is characterized by developmental delay, postnatal growth above the mean, characteristic facial features, and abnormal male genitalia. Moreover, a frequent deletion in the 3q13.31 chromosome region has been identified in patients who are affected by osteosarcomas. Among the genes located within the deleted region, the involvement of the limbic system-associated membrane protein gene (LSAMP), together with a non-coding RNA tumor suppressor candidate 7 gene (TUSC7), has been suggested. We describe the case of an adult acute myeloid leukemia (AML) patient with a novel chromosomal rearrangement characterized by a 3q13.31 microdeletion and an extra copy of the 3q13.31-q29 chromosomal region translocated to the long arm of the Y chromosome. This karyotypic aberration seems to cause LSAMP and TUSC7 gene expression dysregulation. In conclusion, we report the first case of LSAMP and TUSC7 gene overexpression, possibly due to a position effect in an AML patient bearing a 3q13.31 cryptic deletion., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Leukoencephalopathies are heterogeneous entities with white matter abnormalities. Mutations of the gene encoding hepatic and glial cell adhesion molecule (HEPACAM) located on 11q24 are related to one of the leukoencephalopathies: megalencephalic leukoencephalopathy with subcortical cysts type 2 (MLC2). Genomic copy number aberrations were analyzed by microarray comparative hybridization for two patients. One patient who presented with abnormal intensity of the white matter had been previously been diagnosed with the typical genotype and phenotype of Jacobsen syndrome due to an 11q subtelomere deletion, which was further characterized here. In a second patient who exhibited the characteristic finding of leukoencephalopathy, an interstitial deletion of 11q24 was also identified. HEPACAM was involved in both deletions. We therefore suggest that haploinsufficiency of HEPACAM, a gene previously associated with the features of MLC2 and located on the overlapping deletion region between the two patients, might be related to the observed white matter abnormalities., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Objective: The purpose of this study was to estimate the performance of a single-nucleotide polymorphism (SNP)-based noninvasive prenatal test for 5 microdeletion syndromes., Study Design: Four hundred sixty-nine samples (358 plasma samples from pregnant women, 111 artificial plasma mixtures) were amplified with the use of a massively multiplexed polymerase chain reaction, sequenced, and analyzed with the use of the Next-generation Aneuploidy Test Using SNPs algorithm for the presence or absence of deletions of 22q11.2, 1p36, distal 5p, and the Prader-Willi/Angelman region., Results: Detection rates were 97.8% for a 22q11.2 deletion (45/46) and 100% for Prader-Willi (15/15), Angelman (21/21), 1p36 deletion (1/1), and cri-du-chat syndromes (24/24). False-positive rates were 0.76% for 22q11.2 deletion syndrome (3/397) and 0.24% for cri-du-chat syndrome (1/419). No false positives occurred for Prader-Willi (0/428), Angelman (0/442), or 1p36 deletion syndromes (0/422)., Conclusion: SNP-based noninvasive prenatal microdeletion screening is highly accurate. Because clinically relevant microdeletions and duplications occur in >1% of pregnancies, regardless of maternal age, noninvasive screening for the general pregnant population should be considered., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Prenatal sonographic diagnosis of Optiz G/BBB syndrome is difficult because the common clinical features, such as hypertelorism, hypospadias and abnormalities of midline structures, including laryngotracheoesophageal defects, are subtle., Method: Chromosomal microarray (CMA) analysis using a target enriched Fetal DNA Chip design was performed on the DNA of a fetus with congenital cardiac abnormalities., Results: Fetal DNA chip revealed a 48Kb single copy number loss within chromosome region Xp22.2 (arr[hg18]Xp22.2(10,627,354-10,675,946)x0 mat). This deletion included the 3' UTR region of the MID1 gene predicted to cause the X-linked Opitz G/BBB syndrome., Conclusions: This case supports the use of CMA in prenatal diagnosis of fetuses with congenital heart disease. CMA allows prenatal diagnosis of genomic aberrations at a much higher resolution compared with conventional karyotyping, and such findings enable proper genetic counseling and decision making in the pregnancy., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Microdeletions in the 15q22 region have not been well documented. We collected genotype and phenotype data from five patients with microdeletions involving 15q22.2, which were between 0.7 Mb and 6.5 Mb in size; two were of de novo origin and one was of familial origin. Intellectual disability and epilepsy are frequently observed in patients with 15q22.2 deletions. Genotype-phenotype correlation analysis narrowed the critical region for such neurologic symptoms to a genomic region of 654 Kb including the NMDA receptor-regulated 2 gene (NARG2) and the PAR-related orphan receptor A gene (RORA), either of which may be responsible for neurological symptoms commonly observed in patients with deletions in this region. The neighboring regions, including the forkhead box B1 gene (FOXB1), may also be related to the additional neurological features observed in the patients with larger deletions., (Crown Copyright © 2014. Published by Elsevier Masson SAS. All rights reserved.)

Background: Chromosome 1p31 deletion (OMIM #613735) involving the NFIA gene (OMIM 600727) is characterised by variable defects in the formation of the corpus callosum, craniofacial abnormalities and urinary tract defects. A review of current literature suggests only seven cases have been reported, none of which had an isolated NFIA gene defect., Methods: We submit the clinical and molecular features of an 8-year-old female patient with a microdeletion of chromosome 1p31.3 who has developmental delay, metopic synostosis and macroscopic haemoglobinuria. She was investigated with karyotyping, subtelomeric FISH and microarray CGH., Results: Array CGH identified a single 120 kb microdeletion of 1p31.3 involving exons 4-9 of the NFIA gene. Her brain MRI showed hypoplasia of the corpus callosum especially in the posterior areas. Karyotype was normal, ruling out structural chromosomal abnormalities., Conclusion: In this study, we confirmed that a microdeletion in the chromosome region 1p31.3 involving the NFIA gene is associated with hypoplasia of the corpus callosum, developmental delay, metopic synostosis and urinary tract abnormalities. Furthermore, we propose a mechanism by which disruptions in the NFIA gene causes craniofacial abnormalities. This report presents the first case of an intragenic deletion within the NFIA gene that is still consistent with classic clinical phenotypes present in previously reported cases of chromosome 1p31.3 related deletion. This finding will help clarify the role of the NFIA gene in the normal formation of parts of the CNS, the craniofacial complex and the urinary tract., (Crown Copyright © 2014. Published by Elsevier Masson SAS. All rights reserved.)