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Background: Hereditary transthyretin (ATTRv) amyloidosis is a rare, adult-onset autosomal-dominant disorder caused by pathogenic variants in the transthyretin (TTR) gene. Data about relevant variants in specific populations and typical initial manifestations may facilitate early diagnosis and treatment. We here describe the genetic landscape of ATTRv amyloidosis in Israel., Methods: Genetic and clinical data of TTR variant carriers and ATTRv amyloidosis patients were collected from a national referral clinic and other subspecialty clinics in Israel. Genotype-phenotype correlations of the detected variants were detailed. In addition, two large Israeli exome sequence (ES) databases were screened for TTR variants., Results: Seven heterozygous disease-causing variants in TTR were identified among 95 adults (52 males, 50.7%). The Ser77Tyr variant was found in 68 (71.6%) subjects of Jewish Yemenite ancestry. Val122Ile was found in 9 (9.4%) subjects and was the only variant detected in individuals of Arab ethnicity. Other variants were Thr60Ala, Val30Met, Val32Ala, Ala81Val, and Glu89Val. Thirty-five individuals were ATTRv amyloidosis patients (25 males, 71.4%), diagnosed at a mean age of 62.5 ± 6.7 years, and 23 (63.7%) were due to Ser77Tyr. Initial symptoms were mostly related to carpal tunnel syndrome, and the sensitivity of scintigraphy was low for Ser77Tyr but high for Thr60Ala and Val32Ala variants. TTR pathogenic variants were detected in 14 of approximately 36,600 subjects who underwent ES, including Val122Ile in 9 subjects of Arab ethnicity., Conclusions: Most ATTRv amyloidosis cases in Israel are attributable to the Ser77Tyr variant. However, other variants also contribute to disease occurrence, and testing is warranted in clinically suspected patients., (© 2025 The Author(s). European Journal of Neurology published by John Wiley & Sons Ltd on behalf of European Academy of Neurology.)

Objective: To investigate how many novel pathogenic (P) and likely pathogenic (LP) nonprotein-truncating or noncanonical splicing variants would be classified as variants of unknown significance (VUS) if they were detected in fetuses without abnormalities., Methods: The study included 156 patients with neurodevelopmental disorders diagnosed through postnatal exome sequencing. Causative P/LP nonprotein-truncating and noncanonical splicing variants were retrospectively reclassified in cases without specific prenatal manifestations, disregarding postnatal symptoms., Results: Of the 156 patients, 72 had a nontruncating or noncanonical splicing variant. Six patients were excluded for having more than one possible causative variant. Twelve patients had prenatal malformations known to be associated with the diagnosed disorder; therefore, variant interpretation remained unchanged. In 33 of the 54 remaining cases, the variant had been previously reported as P/LP. Reclassification of the other 21 LP/P variants revealed that 16 would have been classified as VUS if detected prenatally., Conclusion: In our cohort, ∼24% (16/66) of causative nonprotein-truncating/noncanonical splicing variants would have been classified as VUS if sequencing had been conducted during pregnancy. The potential for false-negative results, stemming from limitations in the phenotypic information available prenatally, should be discussed with prospective parents. The criteria for classifying and reporting variants in the prenatal setting may require adjustment., (© 2024 John Wiley & Sons Ltd.)

Taliglucerase alfa is an enzyme replacement therapy approved for Gaucher disease. We assessed the duration/compliance/safety of such home infusions in commercial use in four countries where home infusion programs are available. The treatment duration/compliance study included 173 patients (Israel, 58; US, 61; Brazil, 48; Australia, 6) who received ≥1 taliglucerase alfa home infusion through 6/2021. The median age at home therapy initiation was 38 (range, 2-87) years; 58% were females. The median treatment duration (at home) was 2.7 (range, 0.04-9.0) years. The annual compliance rate was stable (≥95%) throughout the study period. A search of the Pfizer global safety database (through 6/2021), identified 19 adverse events (AEs) as related to "definite home use" and 14 to "possible home use" of taliglucerase alfa; 42.4% of these AEs were serious; none were fatal. Twelve serious AEs in five separate case reports were considered treatment related: one case of chest discomfort/pain and hypertension and one case of erythema associated with a toe blister, for which causality could not be excluded; pain in extremity; projectile vomiting and chills, alongside excessive eye blinking; and an infusion-related AE (pruritus). In conclusion, this real-life global study demonstrated that taliglucerase alfa home infusions are safe with high compliance rates.

Purpose: Exome sequencing (ES) could detect pathogenic variants that are unrelated to the test indication, including findings that may have an impact for patients considering conception/reproduction (reproduction-related findings [RRFs]), deliberately searched secondary findings (SFs), and incidental findings (IFs). We aimed to examine the detection rate of clinically actionable findings and to present counseling dilemmas in 840 parents of probands undergoing clinical trio ES testing., Methods: RRFs/IFs/SFs were actively searched for in the parents as part of ES data analysis. Variants were filtered by frequency, mode of inheritance, ClinVar classification, presence in local pathogenic variant databases, and protein-truncating effect., Results: In 14 of 420 families (3.3%), 15 RRFs were detected. Shared parental heterozygous status for autosomal recessive disorders was identified in 23.3% of consanguineous and 1.8% of nonconsanguineous couples. SFs were found in 22 of 840 individuals (2.6%), including 15 variants (7 founder variants) in cancer-predisposing genes and 4 in cardiac disease-related genes. IFs were found in 3 individuals without reported symptoms. Overall, variants of potential medical importance were detected in 9.3% of families. Challenges related to the decision whether to report variants included unreported parental phenotype, presymptomatic testing, variable disease expressivity, potential medical implications for children who are already born, and medicolegal aspects., Conclusion: Active search for RRFs, IFs, and SFs yields a high rate of findings, which may contribute to individual medical care in parents of probands undergoing ES. A structured approach to overcome the challenges associated with reporting these findings should be considered before such an active search can be broadly adopted in clinical genomic data analysis., Competing Interests: The authors declare no conflicts of interest., (© 2023 The Authors.)

Objective: Prenatal exome sequencing (ES) is currently indicated for fetal malformations. Some neurocognitive genetic disorders may not have a prenatal phenotype. We assessed the prevalence of prenatally detectable phenotypes among patients with neurocognitive syndromes diagnosed postnatally by ES., Methods: The medical files of a cohort of 138 patients diagnosed postnatally with a neurocognitive disorder using ES were reviewed for prenatal sonographic data. The Online Mendelian Inheritance in Man (OMIM) database was searched for prenatally detectable phenotypes for all genes identified., Results: Prenatal imaging data were available for 122 cases. Of these, 29 (23.75%) had fetal structural abnormalities and another 29 had other ultrasound abnormalities (fetal growth restriction, polyhydramnios, elevated nuchal translucency). In 30 patients, structural aberrations that were not diagnosed prenatally were detected at birth; in 21 (17.2%), the abnormalities could theoretically be detected prenatally by third-trimester/targeted scans. According to OMIM, 55.9% of the diagnosed genes were not associated with structural anomalies., Conclusions: Most patients (52.5%) with postnatally diagnosed neurocognitive disorders did not have prenatal sonographic findings indicating prenatal ES should be considered. The prevalence of specific prenatal phenotypes such as fetal growth restriction and polyhydramnios in our cohort suggests that additional prenatal findings should be assessed as possible indications for prenatal ES., (© 2022 The Authors. Prenatal Diagnosis published by John Wiley & Sons Ltd.)

Background and Purpose: Muscular A-type lamin-interacting protein (MLIP) is most abundantly expressed in cardiac and skeletal muscle. In vitro and animal studies have shown its regulatory role in myoblast differentiation and in organization of myonuclear positioning in skeletal muscle, as well as in cardiomyocyte adaptation and cardiomyopathy. We report the association of biallelic truncating variation in the MLIP gene with human disease in five individuals from two unrelated pedigrees., Methods: Clinical evaluation and exome sequencing were performed in two unrelated families with elevated creatine kinase level., Results: Family 1. A 6-year-old girl born to consanguineous parents of Arab-Muslim origin presented with myalgia, early fatigue after mild-to-moderate physical exertion, and elevated creatine kinase levels up to 16,000 U/L. Exome sequencing revealed a novel homozygous nonsense variant, c.2530C>T; p.Arg844Ter, in the MLIP gene. Family 2. Three individuals from two distantly related families of Old Order Amish ancestry presented with elevated creatine kinase levels, one of whom also presented with abnormal electrocardiography results. On exome sequencing, all showed homozygosity for a novel nonsense MLIP variant c.1825A>T; p.Lys609Ter. Another individual from this pedigree, who had sinus arrhythmia and for whom creatine kinase level was not available, was also homozygous for this variant., Conclusions: Our findings suggest that biallelic truncating variants in MLIP result in myopathy characterized by hyperCKemia. Moreover, these cases of MLIP-related disease may indicate that at least in some instances this condition is associated with muscle decompensation and fatigability during low-to-moderate intensity muscle exertion as well as possible cardiac involvement., (© 2021 European Academy of Neurology.)

The role of lysine methyltransferases (KMTs) and demethylases (KDMs) in the regulation of chromatin modification is well-established. Recently, deleterious heterozygous variants in KMT5B were implicated in individuals with intellectual disability (ID) and/or autism spectrum disorder. We describe three unrelated patients with global developmental delay (GDD) or ID, macrocephaly and additional features. Using whole exome sequencing, each of the probands was found to harbor a distinct de novo heterozygous disease-causing variant in KMT5B : c.541C > G (p.His181Asp); c.833A > T (p.Asn278Ile); or c.391_394delAAAG (p.Lys131GlufsTer6). We discuss herein their clinical presentations, and compare them to those of previously reported patients. Furthermore, using a three-dimensional computational model of the KMT5B protein, we demonstrate the predicted structural effects of the two missense variants. Our findings support the role of de novo missense and nonsense variants in KMT5B -associated GDD/ID, and suggest that this gene should be considered in the differential diagnosis of neurodevelopmental disorders accompanied by macrocephaly and/or overgrowth., Competing Interests: VK was employed by Bioinformatics Consulting. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Eliyahu, Barel, Greenbaum, Zaks Hoffer, Goldberg, Raas-Rothschild, Singer, Bar-Joseph, Kunik, Javasky, Staretz-Chacham, Pode-Shakked, Bazak, Ruhrman-Shahar, Pras, Frydman, Shohat and Pode-Shakked.)

Competing Interests: The authors declare no conflict of interest.

Purpose: To investigate the effectiveness of phenotype-based search approaches using publicly available online databases., Methods: We included consecutively solved cases from our exome database. For each case, the combination of Human Phenotype Ontology terms reported by the referring clinician was used to perform a search in three commonly used databases: OMIM (first 300 results), Phenolyzer (first 300 results), and Mendelian (all 100 results)., Results: One hundred cases were included (43 females; mean age: 10 years). The actual molecular diagnosis identified through exome sequencing was not included in the search results of any of the queried databases in 33% of cases. In 85% of cases it was not found within the top five search results. When included, its median rank was 61 (range: 1-295), 21 (1-270), and 29 (1-92) in OMIM, Phenolyzer and Mendelian, respectively., Conclusion: This study demonstrates that, in most cases, phenotype-based search approaches using public online databases is ineffective in providing a probable diagnosis for Mendelian conditions. Genotype-first approach through molecular-guided diagnostics with backward phenotyping may be a more appropriate approach for these disorders, unless a specific diagnosis is considered a priori based on highly unique phenotypic features or a specific facial gestalt.

Objective: Laboratories performing prenatal exome sequencing (ES) frequently limit analysis to predetermined gene lists. We used a diagnostic postnatal ES cohort to assess how many of the genes diagnosed are not included in a number of select fixed lists used for prenatal diagnosis., Methods: Of 601 postnatal ES tests, pathogenic variants related to neurodevelopmental disorders were detected in 138 probands. We evaluated if causative genes were present in the following: (1) Developmental Disorders Genotype-Phenotype database list, (2) a commercial laboratory list for prenatal ES, (3) the PanelApp fetal anomalies panel, and (4) a published list used for prenatal diagnosis by ES (Prenatal Assessment of Genomes and Exomes study)., Results: The percentages of cases where the diagnosed gene was not included in the selected four lists were; 11.6%, 17.24%, 23.2%, and 10.9%, respectively. In 13/138 (9.4%) cases, the causative gene was not included in any of the lists; in 4/13 (∼30%) cases noninclusion was explained by a relatively recent discovery of gene-phenotype association., Conclusions: A significant number of genes related to neurocognitive phenotypes are not included in some of the lists used for prenatal ES data interpretation. These are not only genes related to recently discovered disorders, but also genes with well-established gene-phenotype., (© 2021 John Wiley & Sons Ltd.)

The combination of congenital heart defects and vertebral anomalies with or without additional abnormalities has been reported in many genetic disorders. We describe a family in which four consecutive pregnancies were characterized by the combination of fetal congenital heart malformations and vertebral anomalies. In addition, preaxial polydactyly was detected in one of the fetuses. Reanalysis of the non-diagnostic clinical exome data revealed compound heterozygous variants c.350del, p.(Gly117AlafsTer90) and c.757G > T, p.(Asp253Tyr) in ETV2 which have previously not been known to be associated with a phenotype in humans. In mice, Etv2 encodes an obligatory transcription factor involved in the generation of hematopoietic and endothelial cells. Its homozygous disruption results in embryonic lethality due to severe blood and vessel defects. The Etv2 promoter may be bound by Nkx2-5, a key transcription factor in heart development. Pathogenic variants in the NKx2-5 homolog in humans (NKX2-5) are related to congenital heart defects. The identification of additional fetuses or live-born individuals with biallelic pathogenic variants in ETV2 will shed further light on this presumably novel gene-phenotype association and on the full phenotypic spectrum., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

Purpose: Clinical data provided to genetic testing laboratories are frequently scarce. Our purpose was to evaluate clinical scenarios where phenotypic refinement in proband's family members might impact exome data interpretation., Methods: Of 614 exomes, 209 were diagnostic and included in this study. Phenotypic information was gathered by the variant interpretation team from genetic counseling letters and images. If a discrepancy between reported clinical findings and presumably disease-causing variant segregation was observed, referring clinicians were contacted for phenotypic clarification., Results: In 16/209 (7.7%) cases, phenotypic refinement was important due to (1) lack of cosegregation of disease-causing variant with the reported phenotype; (2) identification of different disorders with overlapping symptoms in the same family; (3) similar features in proband and family members, but molecular cause identified in proband only; and (4) previously unrecognized maternal condition causative of child's phenotype. As a result of phenotypic clarification, in 12/16 (75%) cases definition of affected versus unaffected status in one of the family members has changed, and in one case variant classification has changed., Conclusion: Detailed description of phenotypes in family members including differences in clinical presentations, even if subtle, are important in exome interpretation and should be communicated to the variant interpretation team.

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., (© 2020 John Wiley & Sons A/S . Published by John Wiley & Sons Ltd.)

Biallelic mutations in any of the four mismatch repair genes MSH2 , MSH6 , MLH1 and PMS2 result in one of the most aggressive childhood cancer predisposition syndromes, termed constitutional mismatch repair deficiency (CMMRD) syndrome. In addition to a very high tumour risk, the CMMRD phenotype is often characterised by the presence of signs reminiscent of neurofibromatosis type 1. Although paediatric systemic lupus erythematosus (pSLE) has been reported so far in three patients with CMMRD, it has not been considered a diagnostic feature of the syndrome. We report here two additional female patients with pSLE and CMMRD due to biallelic pathogenic variants in MSH6 Hence, there are a total of five out of approximately 200 (2.5%) currently reported patients with CMMRD that also have pSLE, suggesting pSLE should raise the suspicion of a diagnosis of CMMRD, especially if supported by additional indicative features., Competing Interests: Competing interests: ARS and CG-J are full-time employees of the Regeneron Genetics Center from Regeneron Pharmaceuticals Inc. and receive stock options as part of compensation., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

We report 281 individuals carrying a pathogenic recurrent NF1 missense variant at p.Met1149, p.Arg1276, or p.Lys1423, representing three nontruncating NF1 hotspots in the University of Alabama at Birmingham (UAB) cohort, together identified in 1.8% of unrelated NF1 individuals. About 25% (95% confidence interval: 20.5-31.2%) of individuals heterozygous for a pathogenic NF1 p.Met1149, p.Arg1276, or p.Lys1423 missense variant had a Noonan-like phenotype, which is significantly more compared with the "classic" NF1-affected cohorts (all p < .0001). Furthermore, p.Arg1276 and p.Lys1423 pathogenic missense variants were associated with a high prevalence of cardiovascular abnormalities, including pulmonic stenosis (all p < .0001), while p.Arg1276 variants had a high prevalence of symptomatic spinal neurofibromas (p < .0001) compared with "classic" NF1-affected cohorts. However, p.Met1149-positive individuals had a mild phenotype, characterized mainly by pigmentary manifestations without externally visible plexiform neurofibromas, symptomatic spinal neurofibromas or symptomatic optic pathway gliomas. As up to 0.4% of unrelated individuals in the UAB cohort carries a p.Met1149 missense variant, this finding will contribute to more accurate stratification of a significant number of NF1 individuals. Although clinically relevant genotype-phenotype correlations are rare in NF1, each affecting only a small percentage of individuals, together they impact counseling and management of a significant number of the NF1 population., (© 2019 The Authors. Human Mutation Published by Wiley Periodicals, Inc.)

Purpose: Reanalysis of exome sequencing data when results are negative may yield additional diagnoses. We sought to estimate the contribution of clinical geneticists to the interpretation of sequencing data of their patients., Methods: The cohort included 84 probands attending a tertiary genetics institute (2015-2018) with a nondiagnostic result on clinical exome sequencing performed in one of five external laboratories. The raw data were uploaded to the Emedgene bioinformatics and interpretation platform for reanalysis by a team of two clinical geneticists, the geneticist directly involved in the patient's care, and a bioinformatician., Results: In ten probands (11.9%), a new definitive diagnosis was reached based on genes that were known to be associated with the phenotype at the time the original report was issued. The main reasons for a negative exome result were incorrect interpretation of the clinical context and absence of OMIM entry. Pathogenic variants in genes with previously unknown gene-disease associations were discovered to be causative in three probands. In total, new diagnoses were established in 13/84 individuals (15.5%)., Conclusion: Direct access to complete clinical data and shortening of time to including gene-phenotype associations in databases can assist the analytics team and reduce the need for additional unnecessary tests.

MYH7-related disease (MRD) is the most common hereditary primary cardiomyopathy (CM), with pathogenic MYH7 variants accounting for approximately 40% of familial hypertrophic CMs. MRDs may also present as skeletal myopathies, with or without CM. Since pathogenic MYH7 variants result in highly variable clinical phenotypes, from mild to fatal forms of cardiac and skeletal myopathies, genotype-phenotype correlations are not always apparent, and translation of the genetic findings to clinical practice can be complicated. Data on genotype-phenotype correlations can help facilitate more specific and personalized decisions on treatment strategies, surveillance, and genetic counseling. We present a series of six MRD pedigrees with rare genotypes, encompassing various clinical presentations and inheritance patterns. This study provides new insights into the spectrum of MRD that is directly translatable to clinical practice., (© 2018 Wiley Periodicals, Inc.)