ClinVar

Description

Variant summary: MSH6 c.3233T>C (p.Val1078Ala) results in a non-conservative amino acid change located in the DNA mismatch repair protein MutS, core domain (IPR007696) of the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 2.8e-05 in 252738 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.3233T>C has been reported in the literature as a VUS in settings of multigene panel testing in an individual affected with Pancreatic Ductal Adenocarcinoma (example, Shindo_2017). These report(s) do not provide unequivocal conclusions about association of the variant with Hereditary Nonpolyposis Colorectal Cancer/Lynch syndrome. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 23621914, 24728327, 28767289). Eight clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation (VUS, n=7; Benign, n=1). Based on the evidence outlined above, the variant was classified as uncertain significance.