Our verdict is Likely benign. Variant got -2 ACMG points: 0P and 2B. BP4_Moderate
The NM_000179.3(MSH6):āc.3686A>Gā(p.Asn1229Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,614,000 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).
MSH6 (HGNC:7329): (mutS homolog 6) This gene encodes a member of the DNA mismatch repair MutS family. In E. coli, the MutS protein helps in the recognition of mismatched nucleotides prior to their repair. A highly conserved region of approximately 150 aa, called the Walker-A adenine nucleotide binding motif, exists in MutS homologs. The encoded protein heterodimerizes with MSH2 to form a mismatch recognition complex that functions as a bidirectional molecular switch that exchanges ADP and ATP as DNA mismatches are bound and dissociated. Mutations in this gene may be associated with hereditary nonpolyposis colon cancer, colorectal cancer, and endometrial cancer. Transcripts variants encoding different isoforms have been described. [provided by RefSeq, Jul 2013]
FBXO11 (HGNC:13590): (F-box protein 11) This gene encodes a member of the F-box protein family which is characterized by an approximately 40 amino acid motif, the F-box. The F-box proteins constitute one of the four subunits of ubiquitin protein ligase complex called SCFs (SKP1-cullin-F-box), which function in phosphorylation-dependent ubiquitination. The F-box proteins are divided into 3 classes: Fbws containing WD-40 domains, Fbls containing leucine-rich repeats, and Fbxs containing either different protein-protein interaction modules or no recognizable motifs. The protein encoded by this gene belongs to the Fbxs class. It can function as an arginine methyltransferase that symmetrically dimethylates arginine residues, and it acts as an adaptor protein to mediate the neddylation of p53, which leads to the suppression of p53 function. This gene is known to be down-regulated in melanocytes from patients with vitiligo, a skin disorder that results in depigmentation. Polymorphisms in this gene are associated with chronic otitis media with effusion and recurrent otitis media (COME/ROM), a hearing loss disorder, and the knockout of the homologous mouse gene results in the deaf mouse mutant Jeff (Jf), a single gene model of otitis media. Alternatively spliced transcript variants encoding distinct isoforms have been identified for this gene. [provided by RefSeq, Jun 2010]
Uncertain significance, criteria provided, single submitter
clinical testing
Counsyl
Mar 07, 2018
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Uncertain significance, criteria provided, single submitter
clinical testing
Myriad Genetics, Inc.
Mar 29, 2023
This variant is classified as a variant of uncertain significance as there is insufficient evidence to determine its impact on protein function and/or cancer risk. -
not specified Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Mar 20, 2022
Variant summary: MSH6 c.3686A>G (p.Asn1229Ser) results in a conservative amino acid change located in the DNA mismatch repair protein MutS, C-terminal domain (IPR000432) 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 2.4e-05 in 251240 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.3686A>G in individuals affected with Lynch Syndrome/Hereditary Nonpolyposis Colorectal Cancer and no experimental evidence demonstrating its impact on protein function have been reported. Four clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -
Lynch syndrome Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
All of Us Research Program, National Institutes of Health
Sep 17, 2023
This missense variant replaces asparagine with serine at codon 1229 of the MSH6 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with MSH6-related disorders in the literature. This variant has been identified in 6/251240 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -
not provided Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
GeneDx
Jan 24, 2024
In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 30798936, 17531815, 21120944) -
Uncertain significance, criteria provided, single submitter
clinical testing
Ambry Genetics
Nov 01, 2024
The p.N1229S variant (also known as c.3686A>G), located in coding exon 8 of the MSH6 gene, results from an A to G substitution at nucleotide position 3686. The asparagine at codon 1229 is replaced by serine, an amino acid with highly similar properties. This amino acid position is not well conserved in available vertebrate species, and serine is the reference amino acid in other vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Endometrial carcinoma Uncertain:1
Uncertain significance, criteria provided, single submitter