rs587778521

chr2-47403196-C-Achr2-47403196-C-Gchr2-47403196-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PM5 PP3

The NM_000251.3(MSH2):c.5C>A(p.Ala2Glu) variant causes a missense change. The variant allele was found at a frequency of 0.000000693 in 1,442,598 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. A2T) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: MSH2 NM_000251.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 5.30

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr2-47403195-G-A is described in Lovd as [Pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.785

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MSH2	NM_000251.3	c.5C>A	p.Ala2Glu	missense_variant	1/16	ENST00000233146.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH2	ENST00000233146.7	c.5C>A	p.Ala2Glu	missense_variant	1/16	1	NM_000251.3	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.93e-7 AC: 1 AN: 1442598 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 715956

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000256

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 21, 2022	This missense variant replaces alanine with glutamic acid at codon 2 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 hereditary cancer 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Sep 19, 2023	The p.A2E variant (also known as c.5C>A), located in coding exon 1 of the MSH2 gene, results from a C to A substitution at nucleotide position 5. The alanine at codon 2 is replaced by glutamic acid, an amino acid with dissimilar properties. 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. -

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Apr 01, 2023

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. 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) performed at Invitae indicates that this missense variant is not expected to disrupt MSH2 protein function. ClinVar contains an entry for this variant (Variation ID: 186298). This variant has not been reported in the literature in individuals affected with MSH2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces alanine, which is neutral and non-polar, with glutamic acid, which is acidic and polar, at codon 2 of the MSH2 protein (p.Ala2Glu). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.89
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.34
Cadd	Pathogenic	26
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.51	D;.;.
Eigen	Uncertain	0.62
Eigen_PC	Uncertain	0.64
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.86	D;D;D
M_CAP	Pathogenic	0.50	D
MetaRNN	Pathogenic	0.78	D;D;D
MetaSVM	Uncertain	0.75	D
MutationAssessor	Benign	1.4	L;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.80	T
PROVEAN	Benign	-2.1	N;.;N
REVEL	Uncertain	0.55
Sift	Uncertain	0.0010	D;.;D
Sift4G	Uncertain	0.0060	D;.;D
Polyphen		1.0	D;.;D
Vest4		0.63
MutPred		0.26		Gain of solvent accessibility (P = 0.0456);Gain of solvent accessibility (P = 0.0456);Gain of solvent accessibility (P = 0.0456);
MVP		0.92
MPC		0.015
ClinPred		0.99	D
GERP RS		5.4
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		2.1
Varity_R		0.90
gMVP		0.69

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: rs587778521; hg19: chr2-47630335; COSMIC: COSV105086102;