7-6002506-A-T

Position:

• chr7-6002506-A-T

Variant summary

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

The NM_000535.7(PMS2):​c.484T>A​(p.Leu162Ile) 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L162F) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PMS2 NM_000535.7 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.411

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	UniProt
PMS2	NM_000535.7	c.484T>A	p.Leu162Ile	missense_variant	5/15	ENST00000265849.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PMS2	ENST00000265849.12	c.484T>A	p.Leu162Ile	missense_variant	5/15	1	NM_000535.7	P3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Feb 04, 2020

This variant is not present in population databases (ExAC no frequency). In summary, this variant has uncertain impact on PMS2 function. The available evidence is currently insufficient to determine its role 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 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 a PMS2-related disease. This sequence change replaces leucine with isoleucine at codon 162 of the PMS2 protein (p.Leu162Ile). The leucine residue is highly conserved and there is a small physicochemical difference between leucine and isoleucine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.020
CADD	Benign	16
DANN	Uncertain	0.99
DEOGEN2	Benign	0.22	T;.;.;.;.;.
Eigen	Benign	-0.50
Eigen_PC	Benign	-0.72
FATHMM_MKL	Uncertain	0.83	D
LIST_S2	Uncertain	0.94	D;D;.;D;.;D
M_CAP	Uncertain	0.087	D
MetaRNN	Uncertain	0.54	D;D;D;D;D;D
MetaSVM	Uncertain	-0.068	T
MutationAssessor	Uncertain	2.1	M;.;.;.;.;M
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Uncertain	0.70	T
PROVEAN	Benign	-1.3	N;N;.;.;.;N
REVEL	Uncertain	0.46
Sift	Benign	0.14	T;T;.;.;.;T
Sift4G	Benign	0.10	T;D;.;.;.;T
Polyphen		0.99	D;D;.;.;D;D
Vest4		0.85
MutPred		0.53		Gain of MoRF binding (P = 0.1019);.;.;.;.;Gain of MoRF binding (P = 0.1019);
MVP		0.79
MPC		0.28
ClinPred		0.89	D
GERP RS		-4.9
Varity_R		0.25
gMVP		0.47

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: rs1554303909; hg19: chr7-6042137;