2-47475049-T-G

Position:

• chr2-47475049-T-G

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1 PM2 PP3_Strong PP5_Very_Strong

The NM_000251.3(MSH2):​c.1784T>G​(p.Leu595Arg) 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. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: MSH2 NM_000251.3 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 7.30

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 16 ACMG points.

• PM1: In a helix (size 24) in uniprot entity MSH2_HUMAN there are 10 pathogenic changes around while only 2 benign (83%) in NM_000251.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.969
• PP5: Variant 2-47475049-T-G is Pathogenic according to our data. Variant chr2-47475049-T-G is described in ClinVar as [Pathogenic]. Clinvar id is 184645.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MSH2	NM_000251.3	c.1784T>G	p.Leu595Arg	missense_variant	12/16	ENST00000233146.7	NP_000242.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MSH2	ENST00000233146.7	c.1784T>G	p.Leu595Arg	missense_variant	12/16	1	NM_000251.3	ENSP00000233146.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Lynch syndrome 1 Pathogenic:1

Likely pathogenic, no assertion criteria provided

clinical testing

University of Washington Department of Laboratory Medicine, University of Washington

Jul 30, 2020

- -

Hereditary nonpolyposis colorectal neoplasms Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Feb 18, 2022

This sequence change replaces leucine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 595 of the MSH2 protein (p.Leu595Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with clinical features of Lynch syndrome (PMID: 12454801, 23990280; Invitae; External communication). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 184645). Advanced modeling of experimental studies (such as gene expression, population dynamics, functional pathways, and cell-cycle effects in cell culture) performed at Invitae indicates that this missense variant is expected to disrupt MSH2 protein function. For these reasons, this variant has been classified as Pathogenic. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 29, 2021

The p.L595R pathogenic mutation (also known as c.1784T>G), located in coding exon 12 of the MSH2 gene, results from a T to G substitution at nucleotide position 1784. The leucine at codon 595 is replaced by arginine, an amino acid with dissimilar properties. This mutation has been identified in three Ashkenazi Jewish families that meet Amsterdam/Bethesda criteria for Lynch syndrome (Ambry internal data, Goldberg et al. Fam Cancer. 2014 Mar;13(1):65-73, Foulkes et al. Am J Hum Genet. 2002 Dec;71(6):1395-412). This mutation was reported in a patient diagnosed with colon cancer at age 62 whose sister had endometrial cancer at age of 50. Tumor studies for this patient showed absent MSH2 by immunohistochemistry (IHC) staining (Goldberg et al. Fam Cancer. 2014 Mar;13(1): 65-73 and personal communications). In another study, this mutation was detected in an individual with colon cancer and two HNPCC related cancers whose tumor studies showed absence of MSH2 protein and microsatellite instability (Foulkes et al. Am J Hum Genet. 2002 Dec; 71(6):1395-412)). This variant co-segregated with disease in five individuals in an Ashkenazi Jewish family where tumor results for three affected individuals in this family showed microsatellite instability and loss of MSH2 protein on IHC (Ambry internal data). 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). Residue 595 is located in a highly conserved region of the Lever Domain in the MSH2 protein and is likely to be involved in stability and/or allosteric function of the protein (Warren JJ et al. Mol. Cell, 2007 May;26:579-92). Based on an internal structural assessment, this alteration likely does disrupt the structure of the lever 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.94
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.49
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.89	D;.;.;.
Eigen	Pathogenic	0.82
Eigen_PC	Pathogenic	0.78
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.96	D;D;D;D
M_CAP	Pathogenic	0.56	D
MetaRNN	Pathogenic	0.97	D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.4	M;.;.;.
PrimateAI	Uncertain	0.55	T
PROVEAN	Pathogenic	-5.2	D;D;.;D
REVEL	Pathogenic	0.97
Sift	Uncertain	0.0010	D;D;.;D
Sift4G	Pathogenic	0.0010	D;D;.;D
Polyphen		0.97	D;.;.;D
Vest4		0.96
MutPred		0.85		Loss of stability (P = 0.0804);.;Loss of stability (P = 0.0804);Loss of stability (P = 0.0804);
MVP		0.96
MPC		0.028
ClinPred		1.0	D
GERP RS		5.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.98
gMVP		0.93

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: rs786201590; hg19: chr2-47702188;