chr7-5977705-CCAGT-TCAGC

Position:

• chr7-5977705-CCAGT-TCAGC

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_000535.7(PMS2):​c.2324_2328delinsGCTGA​(p.Asn775_Trp776delinsSerTer) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 30)
• Consequence: PMS2 NM_000535.7 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.32

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 Pathogenic. Variant got 12 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. There are 44 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 7-5977705-CCAGT-TCAGC is Pathogenic according to our data. Variant chr7-5977705-CCAGT-TCAGC is described in ClinVar as [Pathogenic]. Clinvar id is 525809.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PMS2	NM_000535.7	c.2324_2328delinsGCTGA	p.Asn775_Trp776delinsSerTer	stop_gained	14/15	ENST00000265849.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PMS2	ENST00000265849.12	c.2324_2328delinsGCTGA	p.Asn775_Trp776delinsSerTer	stop_gained	14/15	1	NM_000535.7	P3

Frequencies

GnomAD3 genomes Cov.: 30

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

GnomAD4 genome Cov.: 30

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary nonpolyposis colorectal neoplasms Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 05, 2018

For these reasons, this variant has been classified as Pathogenic. Loss-of-function variants in PMS2 are known to be pathogenic (PMID: 21376568, 24362816). This variant has not been reported in the literature in individuals with PMS2-related disease. ClinVar contains an entry for this variant (Variation ID: 525809). The frequency data for this variant in the population databases (ExAC) is considered unreliable due to the presence of homologous sequence, such as pseudogenes or paralogs, in the genome. This sequence change replaces asparagine with serine at codon 775 and replaces tryptophan with a stop at codon 776 of the PMS2 gene (p.Asn775_Trp776delinsSer*). The asparagine residue at codon 775 is highly conserved and there is a small physicochemical difference between asparagine and serine. This change also creates a premature translational stop signal at codon 776 in the PMS2 gene which is expected to result in an absent or disrupted protein product. -

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: rs1554293959; hg19: chr7-6017336;