rs863224643

chr2-47408554-A-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.365A>T(p.Lys122Met) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. 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. K122E) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: MSH2 NM_000251.3 missense, splice_region
• Scores: Splicing: ADA: 0.9969
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.08

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 chr2-47408554-A-CGG is described in ClinVar as [Pathogenic]. Clinvar id is 428484.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MSH2	NM_000251.3	c.365A>T	p.Lys122Met	missense_variant, splice_region_variant	2/16	ENST00000233146.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH2	ENST00000233146.7	c.365A>T	p.Lys122Met	missense_variant, splice_region_variant	2/16	1	NM_000251.3	P1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 31

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

Mar 24, 2015

In summary, this is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. This variant has not been published in the literature and is not present in population databases. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies. This sequence change replaces lysine with methionine at codon 122 of the MSH2 protein (p.Lys122Met). The lysine residue is highly conserved and there is a moderate physicochemical difference between lysine and methionine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.85
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.41
Cadd	Pathogenic	32
Dann	Uncertain	0.99
DEOGEN2	Uncertain	0.76	D;D;.;.;.
Eigen	Uncertain	0.58
Eigen_PC	Uncertain	0.50
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.96	D;D;D;D;D
M_CAP	Uncertain	0.21	D
MetaRNN	Pathogenic	0.82	D;D;D;D;D
MetaSVM	Uncertain	-0.23	T
MutationAssessor	Uncertain	2.4	M;.;.;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.68	T
PROVEAN	Uncertain	-3.8	D;D;D;.;D
REVEL	Pathogenic	0.85
Sift	Uncertain	0.0020	D;D;D;.;D
Sift4G	Uncertain	0.0030	D;D;D;.;D
Polyphen		1.0	D;.;.;.;D
Vest4		0.82
MutPred		0.56		Loss of catalytic residue at K122 (P = 0.0292);.;.;Loss of catalytic residue at K122 (P = 0.0292);Loss of catalytic residue at K122 (P = 0.0292);
MVP		0.96
MPC		0.029
ClinPred		0.99	D
GERP RS		5.0
Varity_R		0.86
gMVP		0.80

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
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: rs863224643; hg19: chr2-47635693;