2-47466785-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PM5 PP3

The NM_000251.3(MSH2):c.1638G>C(p.Lys546Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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. K546E) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: MSH2 NM_000251.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 3.09

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 Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 9 benign, 15 uncertain in NM_000251.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr2-47466783-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 1716655.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=1}.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.801

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MSH2	NM_000251.3	c.1638G>C	p.Lys546Asn	missense_variant	10/16	ENST00000233146.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH2	ENST00000233146.7	c.1638G>C	p.Lys546Asn	missense_variant	10/16	1	NM_000251.3	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Dec 25, 2015

This sequence change replaces lysine with asparagine at codon 546 of the MSH2 protein (p.Lys546Asn). The lysine residue is highly conserved and there is a moderate physicochemical difference between lysine and asparagine. In summary, this is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. 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 variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a MSH2-related disease. -

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

research

Cancer Genomics Group, Japanese Foundation For Cancer Research

May 01, 2019

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.19	D
BayesDel_noAF	Uncertain	0.030
Cadd	Uncertain	25
Dann	Uncertain	1.0
DEOGEN2	Pathogenic	0.84	D;.;.;.
Eigen	Uncertain	0.56
Eigen_PC	Uncertain	0.48
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.96	D;D;D;D
M_CAP	Uncertain	0.29	D
MetaRNN	Pathogenic	0.80	D;D;D;D
MetaSVM	Uncertain	0.76	D
MutationAssessor	Uncertain	2.7	M;.;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.81	D
PROVEAN	Uncertain	-4.2	D;D;.;D
REVEL	Pathogenic	0.79
Sift	Uncertain	0.027	D;D;.;T
Sift4G	Benign	0.067	T;T;.;T
Polyphen		0.99	D;.;.;D
Vest4		0.92
MutPred		0.63		Gain of catalytic residue at K546 (P = 0.0296);.;Gain of catalytic residue at K546 (P = 0.0296);Gain of catalytic residue at K546 (P = 0.0296);
MVP		0.92
MPC		0.025
ClinPred		0.99	D
GERP RS		3.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.86
gMVP		0.74

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.080		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: rs372350768; hg19: chr2-47693924;