NM_000251.3:c.1316_1318delCTC

Variant names:

• chr2-47445583-ACTC-A
• rs587779082
• NM_000251.3:c.1316_1318delCTC

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PM4_Supporting

The NM_000251.3(MSH2):​c.1316_1318delCTC​(p.Pro439del) variant causes a disruptive inframe deletion change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 33)
• Consequence: MSH2 NM_000251.3 disruptive_inframe_deletion
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2 U:4
• Conservation: PhyloP100: 4.00

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.

• PM1: In a helix (size 18) in uniprot entity MSH2_HUMAN there are 5 pathogenic changes around while only 0 benign (100%) in NM_000251.3
• PM2: Very rare variant in population databases, with high coverage
• PM4: Nonframeshift variant in NON repetitive region in NM_000251.3. Strenght limited to Supporting due to length of the change: 1aa.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MSH2	NM_000251.3	c.1316_1318delCTC	p.Pro439del	disruptive_inframe_deletion	Exon 8 of 16	ENST00000233146.7	NP_000242.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MSH2	ENST00000233146.7	c.1316_1318delCTC	p.Pro439del	disruptive_inframe_deletion	Exon 8 of 16	1	NM_000251.3	ENSP00000233146.2

Frequencies

GnomAD3 genomes Cov.: 33

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:2 Uncertain:4

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Pathogenic:1 Uncertain:1

Sep 19, 2018

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jun 13, 2024

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.1316_1318delCTC variant (also known as p.P439del) is located in coding exon 8 of the MSH2 gene. This variant results from an in-frame CTC deletion of nucleotide positions 1316 through 1318. This variant was detected in individuals who either met Bethesda/Amsterdam criteria for HNPCC/Lynch syndrome with colorectal tumors that demonstrated high microsatellite instability (MSI-H) and/or absent MSH2 protein expression on immunohistochemistry (IHC) (Nagasaka T, et al. Cancer Res. 2010;70(8):3098-108, Jeong SY, et al. Dis. Colon Rectum 2003;46(8):1069-77; Ambry internal data). This amino acid position is highly conserved in available vertebrate species. This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). In addition, this alteration is predicted to be deleterious by in silico analysis (Choi Y et al., PLoS ONE 2012; 7(10):e46688). Based on the majority of available evidence to date, this variant is likely to be pathogenic. -

Lynch syndrome 1 Uncertain:2

Jul 26, 2016

Counsyl

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

May 09, 2023

Myriad Genetics, Inc.

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is classified as a variant of uncertain significance as there is insufficient evidence to determine its impact on protein function and/or cancer risk. -

Rectal neoplasm Pathogenic:1

-

Institute of Human Genetics, University of Wuerzburg

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Nov 13, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant, c.1316_1318del, results in the deletion of 1 amino acid(s) of the MSH2 protein (p.Pro439del), but otherwise preserves the integrity of the reading frame. This variant is not present in population databases (gnomAD no frequency). This variant has been observed in individual(s) with clinical features of Lynch syndrome (PMID: 15365995, 20388775, 31332305). This variant is also known as c.1316_1318delCCT (p.Leu440del). ClinVar contains an entry for this variant (Variation ID: 90623). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. 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. -

Computational scores

Source: dbNSFP v4.3

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: rs587779082; hg19: chr2-47672722;