NM_000179.3:c.3469G>T

Variant names:

• chr2-47804940-G-T
• rs587779264
• NM_000179.3:c.3469G>T

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM2 PP3_Strong PP5_Very_Strong

The NM_000179.3(MSH6):​c.3469G>T​(p.Gly1157Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,822 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MSH6 NM_000179.3 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8
• Conservation: PhyloP100: 9.57

Genes affected

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]

ACMG classification

Verdict is Pathogenic. Variant got 14 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.989
• PP5: Variant 2-47804940-G-T is Pathogenic according to our data. Variant chr2-47804940-G-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 142773.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MSH6	NM_000179.3	c.3469G>T	p.Gly1157Cys	missense_variant	Exon 6 of 10	ENST00000234420.11	NP_000170.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MSH6	ENST00000234420.11	c.3469G>T	p.Gly1157Cys	missense_variant	Exon 6 of 10	1	NM_000179.3	ENSP00000234420.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461822 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727220

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:8

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Pathogenic:2

Mar 07, 2023

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.G1157C pathogenic mutation (also known as c.3469G>T), located in coding exon 6 of the MSH6 gene, results from a G to T substitution at nucleotide position 3469. The glycine at codon 1157 is replaced by cysteine, an amino acid with highly dissimilar properties. This alteration has been identified in several individuals whose Lynch-associated tumor demonstrated high microsatellite instability (MSI-H) and/or isolated loss of MSH6 protein expression on immunohistochemistry (IHC) (Ambry internal data). Based on an internal structural assessment, this alteration disrupts the local structure in the ATPase domain (Warren JJ et al. Mol. Cell. 2007 May;26:579-92). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

Dec 28, 2021

Color Diagnostics, LLC DBA Color Health

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces glycine with cysteine at codon 1157 in the ATPase domain of the MSH6 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been observed in multiple individuals affected with Lynch syndrome-associated cancers (ClinVar submission ID: SCV000624872.7, SCV001446378.1 and SCV000187253.6). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). A different missense variant at this position, p.Gly1157Asp, has been reported to impact MSH6 function in DNA mismatch binding, in vitro mismatch repair and sensitivity to 6-thioguanine assays (PMID: 31965077). Three different amino acid substitutions, aspartic acid, serine and valine, in place of glycine 1157, have been observed in individuals affected with Lynch syndrome-associated cancers (PMID: 24323032, 31391288; Color internal data). These data indicate that glycine at this position is important for MSH6 protein function. Based on the available evidence, this variant is classified as Likely Pathogenic. -

Lynch syndrome 5 Pathogenic:1

Jul 31, 2020

University of Washington Department of Laboratory Medicine, University of Washington

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Endometrial carcinoma;C1833477:Lynch syndrome 5;C5436807:Mismatch repair cancer syndrome 3 Pathogenic:1

Mar 28, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary nonpolyposis colon cancer Pathogenic:1

Dec 21, 2024

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: MSH6 c.3469G>T (p.Gly1157Cys) results in a non-conservative amino acid change located in the PWWP domain of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. Another variant located at the same codon (c.3469G>A, p.Gly1157Ser) has been reported in individuals with MSH6-related consitions and/or colon cancer, supporting the critical relevance of this residue to MSH6 protein function. The variant was absent in 251390 control chromosomes. c.3469G>T has been reported in the literature in individuals with a personal and family history of Lynch Syndrome/Hereditary Nonpolyposis Colorectal Cancer (HNPCC) tested at our laboratory. These data indicate that the variant is likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication has been ascertained (PMID: 28912153) although it was not captured as a case count in the context of this evaluation. ClinVar contains an entry for this variant (Variation ID: 142773). Based on the evidence outlined above, the variant was classified as pathogenic. -

not provided Pathogenic:1

Oct 18, 2023

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 17531815, 21120944, 28912153) -

Hereditary nonpolyposis colorectal neoplasms Pathogenic:1

Dec 12, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with cysteine, which is neutral and slightly polar, at codon 1157 of the MSH6 protein (p.Gly1157Cys). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with clinical features of Lynch syndrome (internal data). Invitae Evidence Modeling of clinical and family history, age, sex, and reported ancestry of multiple individuals with this MSH6 variant has been performed. This variant is expected to be pathogenic with a positive predictive value of at least 99%. This is a validated machine learning model that incorporates the clinical features of 1,370,736 individuals referred to our laboratory for MSH6 testing. ClinVar contains an entry for this variant (Variation ID: 142773). Invitae Evidence Modeling incorporating data from in vitro experimental studies (internal data) indicates that this missense variant is expected to disrupt MSH6 function with a positive predictive value of 95%. For these reasons, this variant has been classified as Pathogenic. -

Endometrial carcinoma Pathogenic:1

Sep 08, 2023

Baylor Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.56
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.64	.;.;D;D;.
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.97
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	1.0	.;D;D;D;D
M_CAP	Pathogenic	0.61	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.4	.;.;.;H;.
PrimateAI	Uncertain	0.69	T
PROVEAN	Pathogenic	-8.5	.;D;.;D;D
REVEL	Pathogenic	0.97
Sift	Pathogenic	0.0	.;D;.;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D
Polyphen		1.0	.;.;.;D;.
Vest4		0.99
MutPred		0.97		.;.;.;Gain of helix (P = 0.2059);.;
MVP		0.99
ClinPred		1.0	D
GERP RS		5.2
RBP_binding_hub_radar		0.97
RBP_regulation_power_radar		2.8
Varity_R		0.99
gMVP		0.96

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs587779264; hg19: chr2-48032079;