7-5978595-C-T

Position:

• chr7-5978595-C-T

Variant summary

Our verdict is Pathogenic. Variant got 22 ACMG points: 22P and 0B. PVS1 PM2 PP3_Strong PP5_Very_Strong

The NM_000535.7(PMS2):​c.2275+1G>A variant causes a splice donor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000693 in 1,443,332 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: PMS2 NM_000535.7 splice_donor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 7.24

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 22 ACMG points.

• PVS1: Splicing variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 7-5978595-C-T is Pathogenic according to our data. Variant chr7-5978595-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 449208.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr7-5978595-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PMS2	NM_000535.7	c.2275+1G>A		splice_donor_variant		ENST00000265849.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PMS2	ENST00000265849.12	c.2275+1G>A		splice_donor_variant		1	NM_000535.7	P3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.93e-7 AC: 1 AN: 1443332 Hom.: 0 Cov.: 31 AF XY: 0.00000139 AC XY: 1 AN XY: 718046

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: 9.10e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:3

Pathogenic, no assertion criteria provided	clinical testing	Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+	-	- -
Pathogenic, no assertion criteria provided	clinical testing	Clinical Genetics Laboratory, Department of Pathology, Netherlands Cancer Institute	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Apr 04, 2017	This variant is denoted PMS2 c.2275+1G>A or IVS13+1G>A and consists of a G>A nucleotide substitution at the +1 position of intron 13 of the PMS2 gene. This variant destroys a canonical splice donor site and is predicted to cause abnormal gene splicing, leading to either an abnormal message that is subject to nonsense-mediated mRNA decay or to an abnormal protein product. This variant has been reported in at least two individuals with Lynch-associated personal and family histories where tumor testing in both individuals reported microsatellite instability and immunohistochemistry showing the presence of MLH1 and the absence of PMS2 (van der Klift 2016). Based on the current evidence, we consider this variant to be pathogenic. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 11, 2022

The c.2275+1G>A intronic pathogenic mutation results from a G to A substitution one nucleotide after coding exon 13 of the PMS2 gene. This alteration has been identified in multiple individuals diagnosed with colorectal cancer that demonstrated microsatellite instability with absent PMS2 protein expression by immunohistochemistry (van der Klift HM et al. Hum. Mutat. 2016 11;37:1162-1179; Wang et al. J. Med. Genet. 2020 07;57(7):487-499), where subsequent RNA analysis demonstrated aberrant PMS2 splicing resulting in a premature termination codon (van der Klift HM et al. Hum. Mutat. 2016 11;37:1162-1179). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). In silico splice site analysis predicts that this alteration will weaken the native splice donor site. In addition to the clinical data presented in the literature, alterations that disrupt the canonical splice site are expected to cause aberrant splicing, resulting in an abnormal protein or a transcript that is subject to nonsense-mediated mRNA decay. Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

Lynch syndrome 4 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Myriad Genetics, Inc.

Sep 22, 2023

This variant is considered likely pathogenic. This variant occurs within a consensus splice junction and is predicted to result in abnormal mRNA splicing of either an out-of-frame exon or an in-frame exon necessary for protein stability and/or normal function. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.32
CADD	Pathogenic	28
DANN	Uncertain	0.99
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.87
FATHMM_MKL	Pathogenic	1.0	D
MutationTaster	Benign	1.0	D;D;D;D;D
GERP RS		5.5

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_DL_spliceai		1.0		Position offset: 1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1554294393; hg19: chr7-6018226;