rs1554297049

Positions:

• chr7-5986760-T-A
• chr7-5986760-T-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_000535.7(PMS2):​c.2005A>T​(p.Ser669Cys) variant causes a missense, splice region change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. 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. S669N) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 7.0e-7 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: PMS2 NM_000535.7 missense, splice_region
• Scores: Splicing: ADA: 0.9999
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 4.28

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 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PMS2	NM_000535.7	c.2005A>T	p.Ser669Cys	missense_variant, splice_region_variant	11/15	ENST00000265849.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PMS2	ENST00000265849.12	c.2005A>T	p.Ser669Cys	missense_variant, splice_region_variant	11/15	1	NM_000535.7	P3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 6.97e-7 AC: 1 AN: 1434922 Hom.: 0 Cov.: 29 AF XY: 0.00 AC XY: 0 AN XY: 712982

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 9.07e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Mar 30, 2016	The p.S669C variant (also known as c.2005A>T), located in coding exon 11 of the PMS2 gene, results from an A to T substitution at nucleotide position 2005. The serine at codon 669 is replaced by cysteine, an amino acid with dissimilar properties. This variant was not reported in population based cohorts in the following databases: Database of Single Nucleotide Polymorphisms (dbSNP), NHLBI Exome Sequencing Project (ESP), and 1000 Genomes Project. In the ESP, this variant was not observed in 6499 samples (12998 alleles) with coverage at this position. To date, this alteration has been detected with an allele frequency of approximately 0.001% (greater than 110000 alleles tested) in our clinical cohort. This amino acid position is highly conserved in available vertebrate species. This alteration is predicted to decrease the efficiency of the native splice donor site by the BDGP and ESEfinder in silico models; however experimental evidence is not currently available. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Aug 12, 2019	This missense variant replaces serine with cysteine at codon 669 of the PMS2 protein. Computational prediction tools and conservation analyses suggest that this variant may have deleterious impact on the protein function. Computational splicing tools suggest that this variant may impact RNA splicing. To our knowledge, functional assays have not been performed for this variant nor has this variant 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). 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. -

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

May 09, 2018

This sequence change replaces serine with cysteine at codon 669 of the PMS2 protein (p.Ser669Cys). The serine residue is moderately conserved and there is a moderate physicochemical difference between serine and cysteine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with PMS2-related disease. ClinVar contains an entry for this variant (Variation ID: 486045). 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: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C15"). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site, but this prediction has not been confirmed by published transcriptional studies. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.096
BayesDel_addAF	Uncertain	0.065	T
BayesDel_noAF	Benign	-0.14
CADD	Pathogenic	32
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.62	D;.;.;.;.
Eigen	Uncertain	0.66
Eigen_PC	Uncertain	0.65
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.86	D;D;.;D;.
M_CAP	Uncertain	0.11	D
MetaRNN	Benign	0.37	T;T;T;T;T
MetaSVM	Benign	-0.58	T
MutationAssessor	Uncertain	2.8	M;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Uncertain	0.57	T
PROVEAN	Uncertain	-3.8	D;D;.;.;.
REVEL	Benign	0.23
Sift	Uncertain	0.0030	D;D;.;.;.
Sift4G	Uncertain	0.0070	D;D;.;.;.
Polyphen		0.99	D;D;.;.;D
Vest4		0.64
MutPred		0.38		Loss of disorder (P = 0.0083);.;.;.;.;
MVP		0.77
MPC		3.2
ClinPred		0.99	D
GERP RS		5.8
Varity_R		0.51
gMVP		0.57

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	1.0
SpliceAI score (max)		0.11		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: rs1554297049; hg19: chr7-6026391;