2-47466740-A-T

Variant names:

• chr2-47466740-A-T
• rs1553366599
• NM_000251.3:c.1593A>T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM1 PM2

The NM_000251.3(MSH2):​c.1593A>T​(p.Lys531Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. K531E) has been classified as Uncertain significance.

• 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: 1.60
• Publications: 0 publications found

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]

MSH2 Gene-Disease associations (from GenCC):

• Lynch syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: G2P, ClinGen, Orphanet
• Lynch syndrome 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Ambry Genetics
• Muir-Torre syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet, G2P
• mismatch repair cancer syndrome 1

  Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• mismatch repair cancer syndrome 2

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• ovarian cancer

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• malignant pancreatic neoplasm

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• prostate cancer

  Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
• rhabdomyosarcoma

  Inheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp
• breast cancer

  Inheritance: AD Classification: NO_KNOWN Submitted by: Ambry Genetics
• hereditary breast carcinoma

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 18 benign, 39 uncertain in NM_000251.3
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MSH2	NM_000251.3	c.1593A>T	p.Lys531Asn	missense_variant	Exon 10 of 16	ENST00000233146.7	NP_000242.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MSH2	ENST00000233146.7	c.1593A>T	p.Lys531Asn	missense_variant	Exon 10 of 16	1	NM_000251.3	ENSP00000233146.2

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

Jul 10, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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 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. ClinVar contains an entry for this variant (Variation ID: 1972232). This sequence change replaces lysine, which is basic and polar, with asparagine, which is neutral and polar, at codon 531 of the MSH2 protein (p.Lys531Asn). 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). -

Hereditary cancer-predisposing syndrome Uncertain:1

May 15, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.K531N variant (also known as c.1593A>T), located in coding exon 10 of the MSH2 gene, results from an A to T substitution at nucleotide position 1593. The lysine at codon 531 is replaced by asparagine, an amino acid with similar properties. In a massively parallel cell-based functional assay testing susceptibility to a DNA damaging agent, 6-thioguanine (6-TG), this variant was determined to be functionally neutral (Jia X et al. Am J Hum Genet, 2021 Jan;108:163-175). This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Based on the available evidence, the clinical significance of this variant remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.89
BayesDel_addAF	Uncertain	0.13	D
BayesDel_noAF	Uncertain	-0.050
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.66	D;.;.;.
Eigen	Uncertain	0.27
Eigen_PC	Uncertain	0.27
FATHMM_MKL	Uncertain	0.90	D
LIST_S2	Uncertain	0.96	D;D;D;D
M_CAP	Benign	0.059	D
MetaRNN	Uncertain	0.57	D;D;D;D
MetaSVM	Benign	-0.32	T
MutationAssessor	Uncertain	2.4	M;.;.;.
PhyloP100		1.6
PrimateAI	Uncertain	0.78	T
PROVEAN	Uncertain	-3.5	D;D;.;D
REVEL	Pathogenic	0.65
Sift	Benign	0.34	T;T;.;T
Sift4G	Benign	0.50	T;T;.;T
Polyphen		1.0	D;.;.;D
Vest4		0.74
MutPred		0.38		Loss of methylation at K531 (P = 0.0144);.;Loss of methylation at K531 (P = 0.0144);Loss of methylation at K531 (P = 0.0144);
MVP		0.94
MPC		0.033
ClinPred		0.99	D
GERP RS		3.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.82
gMVP		0.66
Mutation Taster		=48/52	disease causing

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

Other links and lift over

dbSNP: rs1553366599; hg19: chr2-47693879;