7-5999121-AAC-A

Position:

• chr7-5999121-AAC-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000535.7(PMS2):​c.690_691del​(p.Phe231TrpfsTer17) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,874 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. V230V) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: PMS2 NM_000535.7 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 8.82

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 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 7-5999121-AAC-A is Pathogenic according to our data. Variant chr7-5999121-AAC-A is described in ClinVar as [Pathogenic]. Clinvar id is 421919.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PMS2	NM_000535.7	c.690_691del	p.Phe231TrpfsTer17	frameshift_variant	6/15	ENST00000265849.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PMS2	ENST00000265849.12	c.690_691del	p.Phe231TrpfsTer17	frameshift_variant	6/15	1	NM_000535.7	P3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461874 Hom.: 0 AF XY: 0.00000138 AC XY: 1 AN XY: 727244

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Jan 15, 2020	This variant deletes 2 nucleotides in exon 6 of the PMS2 gene, creating a frameshift and premature translation stop signal. This variant is expected to result in an absent or non-functional protein product. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). Loss of PMS2 function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	May 08, 2023	The c.690_691delGT pathogenic mutation, located in coding exon 6 of the PMS2 gene, results from a deletion of two nucleotides at nucleotide positions 690 to 691, causing a translational frameshift with a predicted alternate stop codon (p.F231Wfs*17). This alteration was identified in Turkish colorectal cancer patients undergoing multigene panel testing for hereditary cancer risk. (Erdem HB et al. Turk J Med Sci, 2020 Jun;50:1015-1021) (Duzkale N et al. J Coll Physicians Surg Pak, 2021 Jul;30:811-816). This variant was identified in 1/383 minority patients with endometrial cancer (Huang M et al. Sci Rep, 2021 Jun;11:11712). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Aug 16, 2016

This deletion of two nucleotides in PMS2 is denoted c.690_691delGT at the cDNA level and p.Phe231TrpfsX17 (F231WfsX17) at the protein level. The normal sequence, with the bases that are deleted in braces, is CTGT[GT]TTGG. The deletion causes a frameshift which changes a Phenylalanine to a Tryptophan at codon 231, and creates a premature stop codon at position 17 of the new reading frame. Although this variant has not, to our knowledge, been reported in the literature, it is predicted to cause loss of normal protein function through either protein truncation or nonsense-mediated mRNA decay. We consider this variant to be pathogenic. -

Hereditary nonpolyposis colorectal neoplasms Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Feb 16, 2017

For these reasons, this variant has been classified as Pathogenic. While this particular variant has not been reported in the literature, loss-of-function variants in PMS2 are known to be pathogenic (PMID: 21376568, 24362816). This sequence change deletes 2 nucleotide from exon 6 of the PMS2 mRNA (c.690_691delGT), causing a frameshift at codon 231. This creates a premature translational stop signal (p.Phe231Trpfs*17) and is expected to result in an absent or disrupted protein product. -

Lynch syndrome 4 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Myriad Genetics, Inc.

Dec 29, 2022

This variant is considered pathogenic. This variant creates a frameshift predicted to result in premature protein truncation. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		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: rs1064795447; hg19: chr7-6038752;