PURPOSE: Nontruncating variants in SMARCA2, encoding a catalytic subunit of SWI/SNF chromatin remodeling complex, cause Nicolaides-Baraitser syndrome (NCBRS), a condition with intellectual disability and multiple congenital anomalies. Other disorders due to SMARCA2 are unknown. METHODS: By next-generation sequencing, we identified candidate variants in SMARCA2 in 20 individuals from 18 families with a syndromic neurodevelopmental disorder not consistent with NCBRS. To stratify variant interpretation, we functionally analyzed SMARCA2 variants in yeasts and performed transcriptomic and genome methylation analyses on blood leukocytes. RESULTS: Of 20 individuals, 14 showed a recognizable phenotype with recurrent features including epicanthal folds, blepharophimosis, and downturned nasal tip along with variable degree of intellectual disability (or blepharophimosis intellectual disability syndrome [BIS]). In contrast to most NCBRS variants, all SMARCA2 variants associated with BIS are localized outside the helicase domains. Yeast phenotype assays differentiated NCBRS from non-NCBRS SMARCA2 variants. Transcriptomic and DNA methylation signatures differentiated NCBRS from BIS and those with nonspecific phenotype. In the remaining six individuals with nonspecific dysmorphic features, clinical and molecular data did not permit variant reclassification. CONCLUSION: We identified a novel recognizable syndrome named BIS associated with clustered de novo SMARCA2 variants outside the helicase domains, phenotypically and molecularly distinct from NCBRS.
- Klíčová slova
- BIS, Nicolaides–Baraitser syndrome, SMARCA2, intellectual disability, neurodevelopmental disorder,
- MeSH
- blefarofimóza * MeSH
- faciální stigmatizace MeSH
- fenotyp MeSH
- hypotrichóza * MeSH
- lidé MeSH
- mentální retardace * genetika MeSH
- transkripční faktory genetika MeSH
- vrozené deformity nohy (od hlezna dolů) MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- SMARCA2 protein, human MeSH Prohlížeč
- transkripční faktory MeSH
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
- Publikační typ
- tisková chyba MeSH
Most genes associated with neurodevelopmental disorders (NDDs) were identified with an excess of de novo mutations (DNMs) but the significance in case-control mutation burden analysis is unestablished. Here, we sequence 63 genes in 16,294 NDD cases and an additional 62 genes in 6,211 NDD cases. By combining these with published data, we assess a total of 125 genes in over 16,000 NDD cases and compare the mutation burden to nonpsychiatric controls from ExAC. We identify 48 genes (25 newly reported) showing significant burden of ultra-rare (MAF < 0.01%) gene-disruptive mutations (FDR 5%), six of which reach family-wise error rate (FWER) significance (p < 1.25E-06). Among these 125 targeted genes, we also reevaluate DNM excess in 17,426 NDD trios with 6,499 new autism trios. We identify 90 genes enriched for DNMs (FDR 5%; e.g., GABRG2 and UIMC1); of which, 61 reach FWER significance (p < 3.64E-07; e.g., CASZ1). In addition to doubling the number of patients for many NDD risk genes, we present phenotype-genotype correlations for seven risk genes (CTCF, HNRNPU, KCNQ3, ZBTB18, TCF12, SPEN, and LEO1) based on this large-scale targeted sequencing effort.
- MeSH
- CCCTC-vazebný faktor genetika MeSH
- DNA vazebné proteiny genetika MeSH
- draslíkový kanál KCNQ3 genetika MeSH
- genetická predispozice k nemoci * MeSH
- genetické asociační studie MeSH
- heterogenní jaderný ribonukleoprotein U genetika MeSH
- kohortové studie MeSH
- lidé MeSH
- mutace MeSH
- mutační analýza DNA MeSH
- neurovývojové poruchy genetika MeSH
- proteiny vázající RNA genetika MeSH
- represorové proteiny genetika MeSH
- studie případů a kontrol MeSH
- transkripční faktory bHLH genetika MeSH
- transkripční faktory genetika MeSH
- vysoce účinné nukleotidové sekvenování MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Názvy látek
- CCCTC-vazebný faktor MeSH
- CTCF protein, human MeSH Prohlížeč
- DNA vazebné proteiny MeSH
- draslíkový kanál KCNQ3 MeSH
- heterogenní jaderný ribonukleoprotein U MeSH
- HNRNPU protein, human MeSH Prohlížeč
- KCNQ3 protein, human MeSH Prohlížeč
- LEO1 protein, human MeSH Prohlížeč
- proteiny vázající RNA MeSH
- represorové proteiny MeSH
- SPEN protein, human MeSH Prohlížeč
- TCF12 protein, human MeSH Prohlížeč
- transkripční faktory bHLH MeSH
- transkripční faktory MeSH
- ZBTB18 protein, human MeSH Prohlížeč
Cystathionine beta-synthase (CBS) deficiency is a rare inherited disorder in the methionine catabolic pathway, in which the impaired synthesis of cystathionine leads to accumulation of homocysteine. Patients can present to many different specialists and diagnosis is often delayed. Severely affected patients usually present in childhood with ectopia lentis, learning difficulties and skeletal abnormalities. These patients generally require treatment with a low-methionine diet and/or betaine. In contrast, mildly affected patients are likely to present as adults with thromboembolism and to respond to treatment with pyridoxine. In this article, we present recommendations for the diagnosis and management of CBS deficiency, based on a systematic review of the literature. Unfortunately, the quality of the evidence is poor, as it often is for rare diseases. We strongly recommend measuring the plasma total homocysteine concentrations in any patient whose clinical features suggest the diagnosis. Our recommendations may help to standardise testing for pyridoxine responsiveness. Current evidence suggests that patients are unlikely to develop complications if the plasma total homocysteine concentration is maintained below 120 μmol/L. Nevertheless, we recommend keeping the concentration below 100 μmol/L because levels fluctuate and the complications associated with high levels are so serious.
- MeSH
- betain metabolismus MeSH
- cystathionin-beta-synthasa nedostatek MeSH
- homocystein metabolismus MeSH
- homocystinurie dietoterapie farmakoterapie MeSH
- lidé MeSH
- methionin metabolismus MeSH
- pyridoxin terapeutické užití MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- systematický přehled MeSH
- Názvy látek
- betain MeSH
- cystathionin-beta-synthasa MeSH
- homocystein MeSH
- methionin MeSH
- pyridoxin MeSH