Bi-allelic loss-of-function variants in WBP4, encoding a spliceosome protein, result in a variable neurodevelopmental syndrome.

Over two dozen spliceosome proteins are involved in human diseases, also referred to as spliceosomopathies. WW domain-binding protein 4 (WBP4) is part of the early spliceosomal complex and has not been previously associated with human pathologies in the Online Mendelian Inheritance in Man (OMIM) database. Through GeneMatcher, we identified ten individuals from eight families with a severe neurodevelopmental syndrome featuring variable manifestations. Clinical manifestations included hypotonia, global developmental delay, severe intellectual disability, brain abnormalities, musculoskeletal, and gastrointestinal abnormalities. Genetic analysis revealed five different homozygous loss-of-function variants in WBP4. Immunoblotting on fibroblasts from two affected individuals with different genetic variants demonstrated a complete loss of protein, and RNA sequencing analysis uncovered shared abnormal splicing patterns, including in genes associated with abnormalities of the nervous system, potentially underlying the phenotypes of the probands. We conclude that bi-allelic variants in WBP4 cause a developmental disorder with variable presentations, adding to the growing list of human spliceosomopathies.

Spectrum of genes for inherited hearing loss in the Israeli Jewish population, including the novel human deafness gene ATOH1.

Mutations in more than 150 genes are responsible for inherited hearing loss, with thousands of different, severe causal alleles that vary among populations. The Israeli Jewish population includes communities of diverse geographic origins, revealing a wide range of deafness-associated variants and enabling clinical characterization of the associated phenotypes. Our goal was to identify the genetic causes of inherited hearing loss in this population, and to determine relationships among genotype, phenotype, and ethnicity. Genomic DNA samples from informative relatives of 88 multiplex families, all of self-identified Jewish ancestry, with either non-syndromic or syndromic hearing loss, were sequenced for known and candidate deafness genes using the HEar-Seq gene panel. The genetic causes of hearing loss were identified for 60% of the families. One gene was encountered for the first time in human hearing loss: ATOH1 (Atonal), a basic helix-loop-helix transcription factor responsible for autosomal dominant progressive hearing loss in a five-generation family. Our results show that genomic sequencing with a gene panel dedicated to hearing loss is effective for genetic diagnoses in a diverse population. Comprehensive sequencing enables well-informed genetic counseling and clinical management by medical geneticists, otolaryngologists, audiologists, and speech therapists and can be integrated into newborn screening for deafness.

Information Women Choose to Receive About Prenatal Chromosomal Microarray Analysis.

OBJECTIVE: To examine the choices of women with both high-risk and low-risk pregnancies who are undergoing prenatal chromosomal microarray analysis in a clinical setting regarding three challenging types of findings: variants of uncertain clinical significance, susceptibility loci for neurodevelopmental disorders, and copy number variants associated with risks for adult-onset conditions. We assessed whether women's choices were associated with indications for testing or with one-on-one pretest genetic counseling. METHODS: In this cross-sectional study, medical records of women who underwent invasive prenatal chromosomal microarray analysis testing (N=1,070) at Hadassah Medical Center between June 2017 and February 2018 were examined for testing indications, choices regarding chromosomal microarray analysis findings, and type of pretest genetic counseling. Multivariable analyses to assess associations with testing indication and prior genetic counseling were carried out using logistic regression models. RESULTS: In total, 56% of women (n=593) chose to be informed of all three types of findings and 20% (n=218) chose not to be informed of any of the findings beyond high-penetrance childhood-onset pathogenic findings. Variants of uncertain clinical significance as a single choice was the least-selected finding (2.5%, n=27). Low-risk pregnancies (ie, those with normal biochemical screening and fetal ultrasound examinations) were associated with increased interest in receiving genetic information about adult-onset conditions (adjusted odds ratio [aOR] 1.7; 95% CI 1.18-2.33) and susceptibility loci (aOR 1.5; 95% CI 1.08-2.10). CONCLUSION: Women with both high-risk and low-risk pregnancies were generally more likely to choose to receive additional genetic information, albeit differences in preferences depend on testing indication and type of pretest counseling.

Is it safe to use lamotrigine during pregnancy? A prospective comparative observational study.

BACKGROUND: Lamotrigine is a second-generation antiepileptic drug, also used as a mood stabilizer. Published data on its use in human pregnancy are largely derived from pregnancy registries. Pregnancy experience in most studies has been reassuring. However, data from the North American Antiepileptic Drug Pregnancy Registry suggested an increased risk for oral clefts. The primary objective of the study was to evaluate the rate of major anomalies after lamotrigine exposure during pregnancy compared with pregnancies of women counseled for nonteratogenic exposure (NTE). METHODS: Callers who contacted the Israeli Teratology Information Service regarding lamotrigine treatment or NTE during pregnancy between 1997 and 2008 were prospectively followed-up. RESULTS: The rate of major congenital anomalies was similar between 218 lamotrigine exposed pregnancies (208 in the first trimester) and 865 NTE-pregnancies. There was no case of oral cleft in the lamotrigine-exposed group. The median lamotrigine dose in the beginning of pregnancy was 200 mg/d. The dose was increased during pregnancy in 29%. The majority of women in the cohort (82%) were treated for neurologic indications, while 18% for psychiatric disorders. Monotherapy was taken by 72%. CONCLUSION: The data available, thus far, on lamotrigine monotherpy-exposed pregnancies are encouraging. However, further studies are needed to determine with greater certainty the overall risk for major anomalies, as well as the specific risk for oral clefts. Based on the current and previously published data, lamotrigine, seems a reasonable alternative for pregnant women when clinically indicated. Birth Defects Research 109:1196-1203, 2017. © 2017 Wiley Periodicals, Inc.

Recurrent TP53 missense mutation in cancer patients of Arab descent.

Hereditary cancer comprises more than 10% of all breast cancer cases. Identification of germinal mutations enables the initiation of a preventive program that can include early detection or preventive treatment and may also have a major impact on cancer therapy. Several recurrent mutations were identified in the BRCA1/2 genes in Jewish populations however, in other ethnic groups in Israel, no recurrent mutations were identified to date. Our group established panel sequencing in cancer patients to identify recurrent, founder, and new mutations in the heterogeneous and diverse populations in Israel, We evaluated five breast cancer patients of Arab descent diagnosed with cancer before the age of 50 years and identified the previously described TP53 mutation, c.541C>T, R181C (rs587782596), in two women from unrelated Arab families. The two probands were diagnosed with breast cancer at a young age (27 and 34 years) and had significant family history spanning a wide range of tumors (breast cancer (BC), papillary thyroid cancer, glioblastoma multiform (GBM), colon cancer and leukemia). The R181C variant is expected to disrupt p53 at the ASPP2 binding domain but not the DNA binding domain and is defined by Clinvar as likely pathogenic and in HGMD as disease mutation. We further tested 85 unrelated Arab cancer patients and father of a BC carrier patient for TP53 c.541C>T using a real time polymerase chain reaction (RT-PCR) approach and identified four additional carriers, two with BC one with lung cancer, and the father of a BC carrier patient, diagnosed with GBM. Another carrier suffering from BC was identified using a Myriad panel, suggesting a recurrent mutation in this population with a frequency of 5/42 (11.9%) of our selected BC patients. We suggest testing Arab women with a breast cancer at a young age, Arab patients with multiple malignancies, or with suggestive family history for TP53 c.541C>T.

The outcome of pregnancy following topiramate treatment: a study on 52 pregnancies.

In spite of a substantial increase in the use of topiramate at child bearing age, very little is known regarding its use in pregnancy. We describe the outcome of 52 pregnancies with 41 liveborn infants from which it seems that topiramate reduces birth weight without decreasing gestational age at delivery, but does not seem to increase the risk for structural defects. There was an increased rate of spontaneous abortions not related to the drug effects.