rs1553353246

chr2-47416405-T-Cchr2-47416405-T-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1 PM2

The NM_000251.3(MSH2):c.1052T>C(p.Met351Thr) variant causes a missense change. The variant allele was found at a frequency of 0.00000274 in 1,461,250 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. M351I) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: MSH2 NM_000251.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 6.09

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 7 benign, 16 uncertain in NM_000251.3
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MSH2	NM_000251.3	c.1052T>C	p.Met351Thr	missense_variant	6/16	ENST00000233146.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH2	ENST00000233146.7	c.1052T>C	p.Met351Thr	missense_variant	6/16	1	NM_000251.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461250 Hom.: 0 Cov.: 30 AF XY: 0.00000275 AC XY: 2 AN XY: 726972

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Feb 19, 2020

This sequence change replaces methionine with threonine at codon 351 of the MSH2 protein (p.Met351Thr). The methionine residue is moderately conserved and there is a moderate physicochemical difference between methionine and threonine. 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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C45"). This variant has not been reported in the literature in individuals with MSH2-related conditions. ClinVar contains an entry for this variant (Variation ID: 489909). This variant is not present in population databases (ExAC no frequency). -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Dec 05, 2023

This missense variant replaces methionine with threonine at codon 351 of the MSH2 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with MSH2-related disorders in the literature. This variant has not been identified 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.18
BayesDel_addAF	Pathogenic	0.20	D
BayesDel_noAF	Uncertain	0.050
Cadd	Benign	20
Dann	Benign	0.95
DEOGEN2	Uncertain	0.71	D;.;.;.
Eigen	Benign	-0.11
Eigen_PC	Benign	0.079
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.80	T;T;D;D
M_CAP	Uncertain	0.092	D
MetaRNN	Uncertain	0.55	D;D;D;D
MetaSVM	Benign	-0.28	T
MutationAssessor	Benign	1.1	L;.;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.70	T
PROVEAN	Uncertain	-3.3	D;D;.;D
REVEL	Uncertain	0.50
Sift	Benign	0.12	T;T;.;T
Sift4G	Benign	0.22	T;T;.;T
Polyphen		0.0040	B;.;.;B
Vest4		0.46
MutPred		0.46		Loss of stability (P = 0.0246);.;Loss of stability (P = 0.0246);Loss of stability (P = 0.0246);
MVP		0.86
MPC		0.0063
ClinPred		0.87	D
GERP RS		5.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.47
gMVP		0.51

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: rs1553353246; hg19: chr2-47643544; COSMIC: COSV99253676;