rs587779067

Positions:

• chr2-47416399-C-G
• chr2-47416399-C-T

Variant summary

Our verdict is Pathogenic. Variant got 20 ACMG points: 20P and 0B. PS1 PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_000251.3(MSH2):​c.1046C>G​(p.Pro349Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★★). Another nucleotide change resulting in same amino acid change has been previously reported as Pathogenicin Lovd. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P349L) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: MSH2 NM_000251.3 missense
• Clinical Significance: Pathogenic reviewed by expert panel P:7
• Conservation: PhyloP100: 7.76

Genes affected

MSH2 (HGNC:7325): (mutS homolog 2) This locus is frequently mutated in hereditary nonpolyposis colon cancer (HNPCC). When cloned, it was discovered to be a human homolog of the E. coli mismatch repair gene mutS, consistent with the characteristic alterations in microsatellite sequences (RER+ phenotype) found in HNPCC. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Apr 2012]

MSH2 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 20 ACMG points.

• PS1: Transcript NM_000251.3 (MSH2) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in Lovd
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr2-47416399-C-T is described in Lovd as [Pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.992
• PP5: Variant 2-47416399-C-G is Pathogenic according to our data. Variant chr2-47416399-C-G is described in ClinVar as [Pathogenic]. Clinvar id is 90513.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr2-47416399-C-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MSH2	NM_000251.3	c.1046C>G	p.Pro349Arg	missense_variant	6/16	ENST00000233146.7	NP_000242.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MSH2	ENST00000233146.7	c.1046C>G	p.Pro349Arg	missense_variant	6/16	1	NM_000251.3	ENSP00000233146.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:7

Revision: reviewed by expert panel

Submissions by phenotype

Lynch syndrome 1 Pathogenic:3

Likely pathogenic, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Jul 31, 2023	This variant is considered likely pathogenic. This variant is expected to disrupt protein structure [Myriad internal data]. Functional studies indicate this variant impacts protein function [PMID: 26951660]. This variant has been reported in multiple individuals with clinical features of gene-specific disease [PMID: 24278394, 21239990]. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Nov 15, 2016	- -
Pathogenic, reviewed by expert panel	research	International Society for Gastrointestinal Hereditary Tumours (InSiGHT)	Oct 10, 2014	Multifactorial likelihood analysis posterior probability >0.99 -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Oct 10, 2022	This missense variant replaces proline with arginine at codon 349 of the MSH2 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). This variant impacts MSH2 function in a 6-thioguanine sensitivity assay in haploid human cells (internally defined LOF score threshold >= 0.88, PMID: 33357406). In mouse embryonic stem cells, the variant resulted in DNA damage resistance and very low protein expression (PMID: 26951660). This variant has been reported in individuals and families affected with Lynch syndrome (PMID: 21239990, 24278394, 27606285, 28874130, 29575718), and in an individual affected with breast cancer (PMID: 27153395) and an unspecified cancer (PMID: 28873162). Other variants at this codon are reported as pathogenic (ClinVar ID: 90514, 422795). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). Based on the available evidence, this variant is classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Aug 02, 2022	The p.P349R pathogenic mutation (also known as c.1046C>G), located in coding exon 6 of the MSH2 gene, results from a C to G substitution at nucleotide position 1046. The proline at codon 349 is replaced by arginine, an amino acid with dissimilar properties. This alteration has been reported in several individuals meeting Amsterdam criteria, including three with MSI-H tumors showing absent MSH2 staining by IHC (Pastrello C et al. Genet. Med. 2011 Feb;13:115-24; Dominguez-Valentin M et al. Front Oncol 2016 Aug;6:189; De Lellis L et al. PLoS ONE 2013 Nov;8:e81194). Functional assays using mouse embryonic stem cells demonstrated fully abrogated MMR activity of the P349R variant (Houlleberghs H et al. Proc. Natl. Acad. Sci. U.S.A. 2016 Apr;113:4128-33). In a massively parallel cell-based functional assay testing susceptibility to a DNA damaging agent, 6-thioguanine (6-TG), this variant was reported to be functionally deleterious (Jia X et al. Am J Hum Genet, 2021 01;108:163-175). This alteration has been classified as pathogenic using the following lines of evidence: in silico prediction models, segregation with disease, clinical phenotype including tumor characteristics, mutation co-occurrence, and functional studies (Thompson BA et al. Hum. Mutat. 2013 Jan;34:200-9; Thompson BA et al. Nat. Genet. 2014 Feb;46:107-15; available at [www.insight-group.org/variants/classifications/]). 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. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Quest Diagnostics Nichols Institute San Juan Capistrano

Nov 14, 2024

The MSH2 c.1046C>G (p.Pro349Arg) variant has been reported in the published literature in individuals with Lynch syndrome (PMID: 29575718 (2018), 28932927 (2018), 28874130 (2017), 27606285 (2016), 24278394 (2013), 21239990 (2011). Functional studies based on cell survival in response to 6-thioguanine treatment indicates this variant has a damaging effect on DNA mismatch repair function (PMID: 33357406 (2021), 26951660 (2016)). At least one other missense variant at this codon (c.1046C>G (p.Pro349Arg), Quest internal data, ClinVar Variation ID: 90513 and c.1046C>T (p.Pro349Leu), Quest internal data, ClinVar Variation ID: 90514) is considered to be pathogenic or likely pathogenic, suggesting this variant may also cause disease. This variant has not been reported in large, multi-ethnic general populations (Genome Aggregation Database, http://gnomad.broadinstitute.org). Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded predictions that this variant is damaging. Based on the available information, this variant is classified as pathogenic. -

Hereditary nonpolyposis colorectal neoplasms Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 25, 2023

For these reasons, this variant has been classified as Pathogenic. Experimental studies have shown that this missense change affects MSH2 function (PMID: 26951660). Advanced modeling performed at Invitae incorporating data from internal and/or published experimental studies (PMID: 33357406) indicates that this missense variant is expected to disrupt MSH2 function. ClinVar contains an entry for this variant (Variation ID: 90513). This missense change has been observed in individuals with Lynch syndrome (PMID: 21239990, 24278394, 27606285). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces proline, which is neutral and non-polar, with arginine, which is basic and polar, at codon 349 of the MSH2 protein (p.Pro349Arg). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.59	D
BayesDel_noAF	Pathogenic	0.61
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.94	D;.;.;.
Eigen	Pathogenic	0.93
Eigen_PC	Pathogenic	0.84
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D;D;D;D
M_CAP	Pathogenic	0.80	D
MetaRNN	Pathogenic	0.99	D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.6	H;.;.;.
PrimateAI	Pathogenic	0.81	D
PROVEAN	Pathogenic	-8.9	D;D;.;D
REVEL	Pathogenic	0.98
Sift	Pathogenic	0.0	D;D;.;D
Sift4G	Pathogenic	0.0	D;D;.;D
Polyphen		1.0	D;.;.;D
Vest4		0.98
MutPred		0.94		Gain of MoRF binding (P = 0.0106);.;Gain of MoRF binding (P = 0.0106);Gain of MoRF binding (P = 0.0106);
MVP		0.98
MPC		0.035
ClinPred		1.0	D
GERP RS		5.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.99
gMVP		0.82

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: rs587779067; hg19: chr2-47643538;