7-5997349-GG-CA

Position:

• chr7-5997349-GG-CA

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP6

The NM_000535.7(PMS2):​c.779_780delinsTG​(p.Ser260Leu) 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. S260C) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 27)
• Consequence: PMS2 NM_000535.7 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3 B:2
• Conservation: PhyloP100: 0.588

Genes affected

PMS2 (HGNC:9122): (PMS1 homolog 2, mismatch repair system component) The protein encoded by this gene is a key component of the mismatch repair system that functions to correct DNA mismatches and small insertions and deletions that can occur during DNA replication and homologous recombination. This protein forms heterodimers with the gene product of the mutL homolog 1 (MLH1) gene to form the MutL-alpha heterodimer. The MutL-alpha heterodimer possesses an endonucleolytic activity that is activated following recognition of mismatches and insertion/deletion loops by the MutS-alpha and MutS-beta heterodimers, and is necessary for removal of the mismatched DNA. There is a DQHA(X)2E(X)4E motif found at the C-terminus of the protein encoded by this gene that forms part of the active site of the nuclease. Mutations in this gene have been associated with hereditary nonpolyposis colorectal cancer (HNPCC; also known as Lynch syndrome) and Turcot syndrome. [provided by RefSeq, Apr 2016]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP6: Variant 7-5997349-GG-CA is Benign according to our data. Variant chr7-5997349-GG-CA is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 182818.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=3, Benign=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PMS2	NM_000535.7	c.779_780delinsTG	p.Ser260Leu	missense_variant	7/15	ENST00000265849.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PMS2	ENST00000265849.12	c.779_780delinsTG	p.Ser260Leu	missense_variant	7/15	1	NM_000535.7	P3

Frequencies

GnomAD3 genomes Cov.: 27

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

GnomAD4 genome Cov.: 27

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2 Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Dec 09, 2023	The c.779_780delCCinsTG variant (also known as p.S260L), located in coding exon 7 of the PMS2 gene, results from an in-frame deletion of CC and insertion of TG at nucleotide positions 779 to 780. This results in the substitution of the serine residue for a leucine residue at codon 260, an amino acid with dissimilar properties. This variant was identified in 1/177 individuals with pancreatic ductal adenocarcinoma undergoing multi-gene panel testing (Cremin C et al. Cancer Med, 2020 06;9:4004-4013). Based on data from gnomAD, the TG allele has an overall frequency of 0.018% (50/282054) total alleles studied. This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive (Choi Y et al. PLoS ONE. 2012; 7(10):e46688). Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Uncertain significance, criteria provided, single submitter	curation	Sema4, Sema4	Jun 24, 2021	- -
Likely benign, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	May 09, 2022	- -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

May 16, 2024

In silico analysis supports a deleterious effect on protein structure/function; Observed in an individual with pancreatic cancer (PMID: 32255556); This variant is associated with the following publications: (PMID: 32255556, 11574484) -

Hereditary nonpolyposis colorectal neoplasms Benign:1

Benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 17, 2024

- -

Computational scores

Source: dbNSFP v4.3

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs730881920; hg19: chr7-6036980;