7-5987503-C-A

Position:

• chr7-5987503-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_000535.7(PMS2):​c.1262G>T​(p.Arg421Leu) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: not found (cov: 31)
• Consequence: PMS2 NM_000535.7 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 3.81

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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PMS2	NM_000535.7	c.1262G>T	p.Arg421Leu	missense_variant	11/15	ENST00000265849.12	NP_000526.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PMS2	ENST00000265849.12	c.1262G>T	p.Arg421Leu	missense_variant	11/15	1	NM_000535.7	ENSP00000265849	P3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Apr 29, 2020

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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with PMS2-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces arginine with leucine at codon 421 of the PMS2 protein (p.Arg421Leu). The arginine residue is weakly conserved and there is a moderate physicochemical difference between arginine and leucine. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Mar 24, 2020

This missense variant replaces arginine with leucine at codon 421 of the PMS2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). Splice site prediction tools suggest that this variant may not impact RNA splicing. To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with hereditary cancer in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Lynch syndrome 4 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

Jul 21, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.50
BayesDel_addAF	Pathogenic	0.19	D
BayesDel_noAF	Uncertain	0.030
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Benign	0.18	T;.;.;.;.
Eigen	Uncertain	0.55
Eigen_PC	Uncertain	0.56
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.94	D;D;.;D;.
M_CAP	Benign	0.053	D
MetaRNN	Uncertain	0.44	T;T;T;T;T
MetaSVM	Uncertain	0.15	D
MutationAssessor	Uncertain	2.1	M;.;.;.;.
MutationTaster	Benign	0.83	D;D;D;D;D
PrimateAI	Benign	0.35	T
PROVEAN	Uncertain	-3.0	D;D;.;.;.
REVEL	Uncertain	0.29
Sift	Benign	0.048	D;D;.;.;.
Sift4G	Benign	0.32	T;T;.;.;.
Polyphen		1.0	D;D;.;.;D
Vest4		0.75
MutPred		0.32		Loss of MoRF binding (P = 0.0255);.;.;.;.;
MVP		0.72
MPC		0.28
ClinPred		0.94	D
GERP RS		5.8
Varity_R		0.15
gMVP		0.51

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.070		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: rs778482303; hg19: chr7-6027134;