rs531276135

chr2-47475183-G-Achr2-47475183-G-Cchr2-47475183-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_000251.3(MSH2):c.1918G>A(p.Ala640Thr) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. 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. A640S) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: MSH2 NM_000251.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.64

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 2 ACMG points.

• 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.1918G>A	p.Ala640Thr	missense_variant	12/16	ENST00000233146.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH2	ENST00000233146.7	c.1918G>A	p.Ala640Thr	missense_variant	12/16	1	NM_000251.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 05, 2018

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 C0"). This variant has not been reported in the literature in individuals with MSH2-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces alanine with threonine at codon 640 of the MSH2 protein (p.Ala640Thr). The alanine residue is weakly conserved and there is a small physicochemical difference between alanine and threonine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.34
BayesDel_addAF	Pathogenic	0.19	D
BayesDel_noAF	Uncertain	0.030
Cadd	Benign	23
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.42	T;.;.;.
Eigen	Benign	0.15
Eigen_PC	Uncertain	0.24
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Uncertain	0.95	D;D;D;D
M_CAP	Uncertain	0.11	D
MetaRNN	Uncertain	0.68	D;D;D;D
MetaSVM	Uncertain	0.11	D
MutationAssessor	Benign	0.90	L;.;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Benign	0.38	T
PROVEAN	Benign	-0.42	N;N;.;N
REVEL	Uncertain	0.60
Sift	Uncertain	0.0010	D;D;.;D
Sift4G	Uncertain	0.0030	D;D;.;D
Polyphen		0.39	B;.;.;P
Vest4		0.61
MutPred		0.74		Loss of sheet (P = 0.1158);.;Loss of sheet (P = 0.1158);Loss of sheet (P = 0.1158);
MVP		0.84
MPC		0.010
ClinPred		0.72	D
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.66
gMVP		0.77

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: rs531276135; hg19: chr2-47702322;