7-5987453-T-C

Position:

• chr7-5987453-T-C

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_000535.7(PMS2):​c.1312A>G​(p.Lys438Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. 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. K438N) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: PMS2 NM_000535.7 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.297

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 Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.05838573).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PMS2	NM_000535.7	c.1312A>G	p.Lys438Glu	missense_variant	11/15	ENST00000265849.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PMS2	ENST00000265849.12	c.1312A>G	p.Lys438Glu	missense_variant	11/15	1	NM_000535.7	P3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251306 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135862

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 6.84e-7 AC: 1 AN: 1461828 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 727220

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

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

May 07, 2021

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 output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The glutamic acid amino acid residue is found in multiple mammalian species, suggesting that this missense change does not adversely affect protein function. These predictions have not been confirmed by published functional studies and their clinical significance is uncertain. 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 lysine with glutamic acid at codon 438 of the PMS2 protein (p.Lys438Glu). The lysine residue is weakly conserved and there is a small physicochemical difference between lysine and glutamic acid. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 13, 2021

The p.K438E variant (also known as c.1312A>G), located in coding exon 11 of the PMS2 gene, results from an A to G substitution at nucleotide position 1312. The lysine at codon 438 is replaced by glutamic acid, an amino acid with similar properties. This amino acid position is poorly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.065
BayesDel_addAF	Benign	-0.23	T
BayesDel_noAF	Benign	-0.57
CADD	Benign	1.9
DANN	Benign	0.31
DEOGEN2	Benign	0.055	T;.;.;.;.
Eigen	Benign	-1.5
Eigen_PC	Benign	-1.5
FATHMM_MKL	Benign	0.077	N
LIST_S2	Benign	0.42	T;T;.;T;.
M_CAP	Benign	0.013	T
MetaRNN	Benign	0.058	T;T;T;T;T
MetaSVM	Benign	-0.69	T
MutationAssessor	Benign	0.90	L;.;.;.;.
MutationTaster	Benign	1.0	N;N;N;N;N
PrimateAI	Benign	0.24	T
PROVEAN	Benign	0.060	N;N;.;.;.
REVEL	Benign	0.054
Sift	Benign	0.95	T;T;.;.;.
Sift4G	Benign	1.0	T;T;.;.;.
Polyphen		0.0020	B;B;.;.;B
Vest4		0.11
MutPred		0.33		Loss of ubiquitination at K438 (P = 0.0039);.;.;.;.;
MVP		0.24
MPC		0.045
ClinPred		0.012	T
GERP RS		-2.7
Varity_R		0.027
gMVP		0.28

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: rs878854033; hg19: chr7-6027084;