NM_000179.3:c.2479A>G

Variant names:

• chr2-47800462-A-G
• rs878853716
• NM_000179.3:c.2479A>G

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_000179.3(MSH6):​c.2479A>G​(p.Asn827Asp) variant causes a missense change. The variant allele was found at a frequency of 0.00000274 in 1,461,526 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: MSH6 NM_000179.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7 B:1
• Conservation: PhyloP100: 6.29

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 Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.36596742).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MSH6	NM_000179.3	c.2479A>G	p.Asn827Asp	missense_variant	Exon 4 of 10	ENST00000234420.11	NP_000170.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MSH6	ENST00000234420.11	c.2479A>G	p.Asn827Asp	missense_variant	Exon 4 of 10	1	NM_000179.3	ENSP00000234420.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000401 AC: 1 AN: 249096 Hom.: 0 AF XY: 0.00000741 AC XY: 1 AN XY: 134952

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000890

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461526 Hom.: 0 Cov.: 34 AF XY: 0.00000275 AC XY: 2 AN XY: 727096

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: 0.00000180

Gnomad4 OTH exome AF: 0.0000331

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:7 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2 Benign:1

Jan 09, 2025

Molecular Diagnostics Laboratory, Catalan Institute of Oncology

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

PM2_Supporting c.2479A>G, located in exon 4 of the MSH6 gene, is predicted to result in the substitution of asparagine by aspartic acid at codon 827, p.(Asn827Asp). This variant is found in 1/234662 alleles at a frequency of 0.0004% in the gnomAD v2.1.1 database, non-cancer dataset (PM2_supporting). In silico analyses are unconclusive regarding the effect this variant may have on protein structure and function (MAPP+PP-2 prior probability for pathogenicity = 0.15). To our knowledge, neither relevant clinical data nor well-stablished functional studies have been reported for this variant. In addition, the variant is reported in the ClinVar database (1x likely benign, 5x uncertain significance), but it is not reported in InSiGHT and LOVD databases. Based on the currently available information, c.2479A>G is classified as an uncertain significance variant according to ClinGen-MMR Guidelines Draft v3.1. -

Aug 28, 2018

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Apr 05, 2023

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces asparagine with aspartic acid at codon 827 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 1/249096 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. -

Lynch syndrome 5 Uncertain:1

May 28, 2019

Mendelics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Lynch syndrome Uncertain:1

May 04, 2023

All of Us Research Program, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces asparagine with aspartic acid at codon 827 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 1/249096 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

Dec 01, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis indicates 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: 17531815, 21120944) -

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Dec 12, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces asparagine, which is neutral and polar, with aspartic acid, which is acidic and polar, at codon 827 of the MSH6 protein (p.Asn827Asp). This variant is present in population databases (no rsID available, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with MSH6-related conditions. ClinVar contains an entry for this variant (Variation ID: 237158). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt MSH6 protein function with a negative predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Endometrial carcinoma Uncertain:1

Jan 16, 2024

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.32
BayesDel_addAF	Benign	-0.043	T
BayesDel_noAF	Benign	-0.30
CADD	Uncertain	23
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.44	.;.;T;T;.
Eigen	Benign	0.022
Eigen_PC	Uncertain	0.22
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.93	.;D;D;D;D
M_CAP	Uncertain	0.18	D
MetaRNN	Benign	0.37	T;T;T;T;T
MetaSVM	Uncertain	-0.017	T
MutationAssessor	Benign	0.20	.;.;N;.;.
PrimateAI	Uncertain	0.56	T
PROVEAN	Benign	-1.0	.;N;N;.;N
REVEL	Uncertain	0.41
Sift	Benign	0.098	.;T;T;.;T
Sift4G	Benign	0.50	T;T;T;T;T
Polyphen		0.061	.;.;B;.;.
Vest4		0.32
MutPred		0.44		.;.;Loss of helix (P = 0.0558);.;.;
MVP		0.90
ClinPred		0.46	T
GERP RS		5.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.8
Varity_R		0.64
gMVP		0.39

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: rs878853716; hg19: chr2-48027601;