ClinVar Genomic variation as it relates to human health

In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; Not observed in large population cohorts (Lek et al., 2016); This variant is associated with the following publications: (PMID: 29907796, 22726846, 25168959)

The heterozygous p.Arg37His variant in SMARCB1 was identified by our study in one individual with Coffin-Siris syndrome. The p.Arg37His variant in SMARCB1 has been reported in >10 individuals with Coffin-Siris syndrome (PMIDs: 22726846, 29907796, 33057194, 34906496, 36964972), but was absent from large population studies. The number of reported affected individuals with this variant is greater than expected compared to non-affected individuals with this variant. This variant has been reported in ClinVar (Variation ID: 88893) and has been interpreted as uncertain significance by two submitters, likely pathogenic by two submitters, and pathogenic by three submitters. This variant is assumed de novo in 11 individuals, but maternity and paternity have not been confirmed (PMIDs: 22726846, 29907796, 34906496, 36964972). Computational prediction tools and conservation analyses suggest that this variant may impact the protein, though this information is not predictive enough to determine pathogenicity. The number of missense variants reported in SMARCB1 in the general population is lower than expected, suggesting there is little benign variation in this gene and slightly increasing the possibility that a missense variant in this gene may not be tolerated. In summary, although additional studies are required to fully establish its clinical significance, this variant is likely pathogenic for autosomal dominant Coffin-Siris syndrome. ACMG/AMP Criteria applied: PM2_Supporting, PS4_Moderate, PP2, PM6, PP3_Moderate (Richards 2015).

This variant is interpreted as Uncertain Significance - Insufficient Evidence, for Coffin-Siris syndrome 3, autosomal dominant. The following ACMG Tag(s) were applied: PM2 => Absent from controls (or at extremely low frequency if recessive) in Exome Sequencing Project, 1000 Genomes Project, or Exome Aggregation Consortium. PM6 => Assumed de novo, but without confirmation of paternity and maternity (https://www.ncbi.nlm.nih.gov/pubmed/22726846).

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0103 - Dominant negative, loss of function and gain of function are all known mechanisms of disease in this gene. Loss of function variants are associated with cancer susceptibility (rhabdoid tumor predisposition syndrome 1 (MIM#609322), schwannomatosis-1 (MIM#162091), rhabdoid tumors somatic (MIM#609322)). An inframe deletion variant, missense variants and truncating variants escaping nonsense-mediated decay have all been reported to have either a gain of function or dominant negative mechanism, and are associated with Coffin-Siris syndrome 3 (MIM#614608) (OMIM, PMID: 31759698). (I) 0107 - This gene is associated with autosomal dominant disease. (I) 0200 - Variant is predicted to result in a missense amino acid change from arginine to histidine. (I) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0502 - Missense variant with conflicting in silico predictions and high conservation. (I) 0603 - Missense variant in a region that is highly intolerant to missense variation (high constraint region in gnomAD). This variant is located in the DNA binding domain (DECIPHER). (SP) 0801 - This variant has strong previous evidence of pathogenicity in unrelated individuals. It has been observed de novo in multiple affected individuals (PMIDs: 29907796, 34906496, 31172278). In addition, it has been reported as pathogenic and likely pathogenic by multiple clinical laboratories (ClinVar). (SP) 1203 - This variant has been shown to be de novo in the proband (parental status confirmed) (by trio analysis). (SP) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign

This variant has been previously reported as disease-causing and was found twice in our laboratory de novo: in a 6-year-old male with global delays, autism spectrum, hypotonia, hydrocephalus, VUR, agenesis of the corpus callosum, myopia, pes cavus, elevated free T4; in an 8-year-old female with intellectual disability, behavior problems, hydrocephalus, dysmorphisms, amblyopia, myopic astigmatixm, hypoplastic labia majora, hypertonia, decreased muscle mass, dysphagia, Wilms tumor