rs863224640

chr2-47475254-G-Achr2-47475254-G-Cchr2-47475254-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 4P and 3B. PM1 PM2 BP4_Moderate BP6

The NM_000251.3(MSH2):c.1989G>A(p.Met663Ile) variant causes a missense change. The variant allele was found at a frequency of 0.000000686 in 1,458,242 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M663V) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: MSH2 NM_000251.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: 4.70

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 1 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 7 benign, 17 uncertain in NM_000251.3
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.22901708).
• BP6: Variant 2-47475254-G-A is Benign according to our data. Variant chr2-47475254-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 216346.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MSH2	NM_000251.3	c.1989G>A	p.Met663Ile	missense_variant	12/16	ENST00000233146.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH2	ENST00000233146.7	c.1989G>A	p.Met663Ile	missense_variant	12/16	1	NM_000251.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250870 Hom.: 0 AF XY: 0.00000737 AC XY: 1 AN XY: 135626

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000881

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.86e-7 AC: 1 AN: 1458242 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 725400

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 9.01e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jan 24, 2024

This sequence change replaces methionine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 663 of the MSH2 protein (p.Met663Ile). This variant is present in population databases (no rsID available, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with MSH2-related conditions. ClinVar contains an entry for this variant (Variation ID: 216346). Advanced modeling performed at Invitae incorporating data from internal and/or published experimental studies (PMID: 33357406) indicates that this missense variant is not expected to disrupt MSH2 function with a negative predictive value of 95%. 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. -

Hereditary cancer-predisposing syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 02, 2022

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.34
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Uncertain	-0.070
Cadd	Benign	22
Dann	Uncertain	0.99
DEOGEN2	Uncertain	0.49	T;.;.;.
Eigen	Benign	0.013
Eigen_PC	Uncertain	0.24
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.94	D;D;D;D
M_CAP	Benign	0.028	D
MetaRNN	Benign	0.23	T;T;T;T
MetaSVM	Benign	-0.46	T
MutationAssessor	Benign	-0.23	N;.;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Benign	0.48	T
PROVEAN	Benign	-1.9	N;N;.;N
REVEL	Uncertain	0.39
Sift	Benign	0.20	T;T;.;T
Sift4G	Benign	0.48	T;T;.;T
Polyphen		0.0050	B;.;.;P
Vest4		0.65
MutPred		0.61		Loss of ubiquitination at K661 (P = 0.0516);.;Loss of ubiquitination at K661 (P = 0.0516);Loss of ubiquitination at K661 (P = 0.0516);
MVP		0.80
MPC		0.0089
ClinPred		0.36	T
GERP RS		6.0
Varity_R		0.23
gMVP		0.52

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs863224640; hg19: chr2-47702393;