2-47410149-T-C

Variant summary

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

The NM_000251.3(MSH2):c.422T>C(p.Met141Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,818 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. M141V) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: MSH2 NM_000251.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5 B:2
• Conservation: PhyloP100: 1.13

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 3 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 10 benign, 16 uncertain in NM_000251.3
• PM2: Very rare variant in population databases, with high coverage
• BP6: Variant 2-47410149-T-C is Benign according to our data. Variant chr2-47410149-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 419266.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=5, Likely_benign=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MSH2	NM_000251.3	c.422T>C	p.Met141Thr	missense_variant	3/16	ENST00000233146.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH2	ENST00000233146.7	c.422T>C	p.Met141Thr	missense_variant	3/16	1	NM_000251.3	P1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251414 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135884

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000109

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461818 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727212

Gnomad4 AFR exome AF: 0.0000597

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000504

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.: 31

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:5 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Oct 26, 2018	This variant is denoted MSH2 c.422T>C at the cDNA level, p.Met141Thr (M141T) at the protein level, and results in the change of a Methionine to a Threonine (ATG>ACG). This variant has not, to our knowledge, been published in the literature as a pathogenic or benign germline variant. MSH2 Met141Thr was observed at an allele frequency of 0.01% (2/17248) in individuals of East Asian ancestry in large population cohorts (Lek 2016). This variant is located in the connector domain (L?tzen 2008, Kansikas 2011). In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect. Based on currently available evidence, it is unclear whether MSH2 Met141Thr is a pathogenic or benign variant. We consider it to be a variant of uncertain significance. -
Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Nov 17, 2017	- -

Hereditary cancer-predisposing syndrome Uncertain:1 Benign:1

Likely benign, criteria provided, single submitter	clinical testing	Ambry Genetics	May 22, 2023	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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Apr 05, 2023	This missense variant replaces methionine with threonine at codon 141 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). This variant does not impact MSH2 function in a 6-thioguanine sensitivity assay in haploid human cells (internally defined LOF score threshold <= -1.32, PMID: 33357406). To our knowledge, this variant has not been reported in individuals affected with MSH2-related disorders in the literature. This variant has been identified in 2/251414 chromosomes 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. -

Lynch syndrome 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

May 25, 2023

- -

Lynch syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

May 04, 2023

This missense variant replaces methionine with threonine at codon 141 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). This variant does not impact MSH2 function in a 6-thioguanine sensitivity assay in haploid human cells (internally defined LOF score threshold <= -1.32, PMID: 33357406). To our knowledge, this variant has not been reported in individuals affected with MSH2-related disorders in the literature. This variant has been identified in 2/251414 chromosomes 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. -

Hereditary nonpolyposis colorectal neoplasms Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Jul 29, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.16
BayesDel_addAF	Uncertain	0.033	T
BayesDel_noAF	Uncertain	0.030
Cadd	Benign	13
Dann	Benign	0.52
DEOGEN2	Uncertain	0.65	D;T;.;.;.
Eigen	Benign	-0.21
Eigen_PC	Benign	-0.15
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Benign	0.57	T;T;T;T;T
M_CAP	Benign	0.052	D
MetaRNN	Uncertain	0.43	T;T;T;T;T
MetaSVM	Uncertain	0.18	D
MutationAssessor	Uncertain	2.3	M;.;.;.;.
MutationTaster	Benign	0.99	D;D;D
PrimateAI	Benign	0.45	T
PROVEAN	Benign	-2.2	N;D;N;.;N
REVEL	Uncertain	0.63
Sift	Benign	0.28	T;T;T;.;T
Sift4G	Benign	0.27	T;T;T;.;T
Polyphen		0.0030	B;.;.;.;B
Vest4		0.44
MutPred		0.63		Gain of catalytic residue at M141 (P = 0.0422);.;.;Gain of catalytic residue at M141 (P = 0.0422);Gain of catalytic residue at M141 (P = 0.0422);
MVP		0.94
MPC		0.0062
ClinPred		0.065	T
GERP RS		3.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.087
gMVP		0.60

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: rs768313658; hg19: chr2-47637288;