2-47806281-C-T

Position:

chr2-47806281-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2PM5PP3_Strong

The NM_000179.3(MSH6):c.3724C>T(p.Arg1242Cys) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,606 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1242H) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 33)

Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

MSH6
NM_000179.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 5.78

Variant links:

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]

MSH6 links:

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]

FBXO11 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr2-47806282-G-A is described in Lovd as [Likely_pathogenic].

PP3

MetaRNN computational evidence supports a deleterious effect, 0.94

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MSH6	NM_000179.3 linkuse as main transcript	c.3724C>T	p.Arg1242Cys	missense_variant	8/10	ENST00000234420.11	NP_000170.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MSH6	ENST00000234420.11 linkuse as main transcript	c.3724C>T	p.Arg1242Cys	missense_variant	8/10	1	NM_000179.3	ENSP00000234420	P4	P52701-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251188

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135746

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000289

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:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000137

AC:

AN:

1461606

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727146

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000224

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.0000187

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Lynch syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Mar 23, 2023

This missense variant replaces arginine with cysteine at codon 1242 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 reported in an individual affected with gastric cancer (PMID: 30680046), and in individuals affected with breast and/or ovarian cancer (PMID: 25186627, 30982232). This variant has been identified in 1/251188 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Different variants affecting the same codon, c.3725G>A (p.Arg1242His), c.3724C>A (p.Arg1242Ser), and c.3724C>G (p.Arg1242Gly), are considered to be disease-causing (ClinVar variation ID: 140866, 89449, 455280), suggesting that arginine at this position is important for the protein function. 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

Aug 17, 2023

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: 25111426, 17531815, 21120944, 25186627, 30680046, 30982232, 31204389, 28514183, 24763289) -

Hereditary nonpolyposis colorectal neoplasms

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 18, 2023

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 1242 of the MSH6 protein (p.Arg1242Cys). This variant is present in population databases (no rsID available, gnomAD 0.003%). 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: 232375). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on MSH6 protein function. This variant disrupts the p.Arg1242 amino acid residue in MSH6. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 24763289, 28514183, 31204389). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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. -

Hereditary cancer-predisposing syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 30, 2024

The p.R1242C variant (also known as c.3724C>T), located in coding exon 8 of the MSH6 gene, results from a C to T substitution at nucleotide position 3724. The arginine at codon 1242 is replaced by cysteine, an amino acid with highly dissimilar properties. This alteration has been identified in an individual diagnosed with diffuse gastric cancer (Henn J et al. Hered Cancer Clin Pract. 2019 Jan;17:5). This alteration was also detected on a 25-gene panel test in a woman who was diagnosed with breast cancer after age 50 (Tung N et al. Cancer. 2015 Jan;121:25-33). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious 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

clinical testing

Baylor Genetics

May 26, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.53

BayesDel_addAF

Pathogenic

0.39

BayesDel_noAF

Pathogenic

0.41

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Benign

0.31

.;.;T;D;.

Eigen

Pathogenic

0.79

Eigen_PC

Pathogenic

0.67

FATHMM_MKL

Uncertain

0.95

LIST_S2

Uncertain

0.95

.;D;D;D;D

M_CAP

Pathogenic

0.33

MetaRNN

Pathogenic

0.94

D;D;D;D;D

MetaSVM

Pathogenic

0.81

MutationAssessor

Pathogenic

3.4

.;.;.;M;.

MutationTaster

Benign

1.0

D;D;D;D

PrimateAI

Pathogenic

0.82

PROVEAN

Pathogenic

-7.5

.;D;.;D;D

REVEL

Pathogenic

0.79

Sift

Pathogenic

0.0

.;D;.;D;D

Sift4G

Pathogenic

0.0010

D;D;D;D;D

Polyphen

1.0

.;.;.;D;.

Vest4

0.93

MutPred

0.79

.;.;.;Loss of catalytic residue at R1242 (P = 0.0752);.;

MVP

0.96

ClinPred

1.0

GERP RS

4.6

Varity_R

0.97

gMVP

0.88

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over