rs587779340

Positions:

• chr7-6003794-T-A
• chr7-6003794-T-C
• chr7-6003794-T-G

Variant summary

Our verdict is Pathogenic. Variant got 20 ACMG points: 20P and 0B. PVS1 PP3_Strong PP5_Very_Strong

The NM_000535.7(PMS2):​c.251-2A>T variant causes a splice acceptor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000442 in 1,582,534 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: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000042 (0 hom.)
• Consequence: PMS2 NM_000535.7 splice_acceptor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:17
• Conservation: PhyloP100: 7.60

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 20 ACMG points.

• PVS1: Splicing variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 7.4, offset of -41, new splice context is: tgtatattttgttgttatAGcac. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• 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 7-6003794-T-A is Pathogenic according to our data. Variant chr7-6003794-T-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 183893.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr7-6003794-T-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PMS2	NM_000535.7	c.251-2A>T		splice_acceptor_variant		ENST00000265849.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PMS2	ENST00000265849.12	c.251-2A>T		splice_acceptor_variant		1	NM_000535.7	P3

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152134 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000409 AC: 1 AN: 244282 Hom.: 0 AF XY: 0.00000751 AC XY: 1 AN XY: 133182

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: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000904

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000419 AC: 6 AN: 1430400 Hom.: 0 Cov.: 26 AF XY: 0.00000701 AC XY: 5 AN XY: 713756

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: 0.00000552

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152134 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74308

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ExAC AF: 0.00000833 AC: 1

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:17

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:4

Pathogenic, no assertion criteria provided	clinical testing	Mayo Clinic Laboratories, Mayo Clinic	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Nov 16, 2020	This variant is located in a canonical splice-acceptor site and interferes with normal PMS2 mRNA splicing. The variant has been reported in individuals with suspected Lynch syndrome in the published literature (PMID: 31992580 (2020), 25980754 (2015)). Based on the available information, this variant is classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jun 10, 2022	Canonical splice site variant predicted to result in a null allele in a gene for which loss-of-function is a known mechanism of disease; Observed in individuals with a personal or family history consistent with pathogenic variants in this gene (Yurgelun 2015, Wang 2020); Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 25980754, 27779110, 26845104, 29625052, 31992580, 31447099, 32719484, 18602922) -
Pathogenic, no assertion criteria provided	clinical testing	Department of Pathology and Laboratory Medicine, Sinai Health System	-	The PMS2 c.251-2A>T variant was identified in 1 of 2520 proband chromosomes (frequency: 0.0004) from individuals or families with Lynch syndrome (Yurgelun 2015). The variant was also identified in dbSNP (ID: rs587779340) as "With Likely pathogenic, Pathogenic allele", ClinVar (classified as pathogenic by Ambry genetics, Invitae, GeneDx and two clinical laboratories; as likely benign by two submitters), and in Insight Hereditary Tumors Database (3x ). The variant was not identified in GeneInsight-COGR, Cosmic, or Mismatch Repair Genes Variant, databases. The variant was identified in control databases in 1 of 239164 chromosomes at a frequency of 0.000004 (Genome Aggregation Database Feb 27, 2017). The variant was observed in the European population in 1 of 108456 chromosomes (freq: 0.000009), while the variant was not observed in the African, Other, Latino, Ashkenazi Jewish, East Asian, Finnish, and South Asian populations. The c.251-2A>T variant is predicted to cause abnormal splicing because the nucleotide substitution occurs in the invariant region of the splice consensus sequence. In addition, 4 of 4 in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) predict a greater than 10% difference in splicing. A different variant affecting this nucleotide (c.251-2A>G) classified as pathogenic, has been found in Lynch syndrome patients as biallelic PMS2 gene mutation (Herkert 2011, Senter 2008). In summary, based on the above information this variant meets our laboratory’s criteria to be classified as pathogenic. -

Lynch syndrome 4 Pathogenic:4

Pathogenic, criteria provided, single submitter	research	HudsonAlpha Institute for Biotechnology, HudsonAlpha Institute for Biotechnology	Sep 14, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Jun 07, 2023	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Feb 16, 2017	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Apr 04, 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. -

Lynch syndrome Pathogenic:3

Likely pathogenic, criteria provided, single submitter	clinical testing	University of Washington Department of Laboratory Medicine, University of Washington	Nov 20, 2015	- -
Pathogenic, criteria provided, single submitter	clinical testing	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	Mar 09, 2018	The c.251-2A>T variant in PMS2 has been reported in one individual with suspecte d Lynch syndrome (Yurgelun 2015) and has also been reported by other clinical la boratories in ClinVar (Variation ID# 183893). Additionally, two other variants a t this position (c.251-2A>C, c.251A>G) have been reported in individuals with PM S2-related cancers (Herkert 2011, Senter 2008), one of which has also been class ified as pathogenic on September 5, 2013 by the ClinGen-approved InSiGHT expert panel (ClinVar SCV000108354.2). The c.251A>T variant has also been identified in 1/108456 European chromosomes by the Genome Aggregation Database (gnomAD, http: //gnomad.broadinstitute.org; dbSNP rs587779340). This frequency is low enough to be consistent with the frequency of Lynch syndrome in the general population. T his variant occurs in the invariant region (+/- 1,2) of the splice consensus seq uence and is predicted to cause altered splicing leading to an abnormal or absen t protein. Heterozygous loss of function of the PMS2 gene is an established dise ase mechanism in individuals with Lynch syndrome. In summary, this variant meets criteria to be classified as pathogenic for Lynch syndrome in an autosomal domi nant manner based upon predicted impact to the protein, very low frequency in th e general population and the presence of a different pathogenic variant at the s ame position. ACMG/AMP criteria applied (Richards 2015): PVS1, PM5, PM2. -
Pathogenic, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Jan 22, 2024	This variant causes an A to T nucleotide substitution at the -2 position of intron 3 of the PMS2 gene. Splice site prediction tools predict that this variant may have a significant impact on RNA splicing. Although this prediction has not been confirmed in published RNA studies, this variant is expected to result in an absent or disrupted protein product. This variant has been reported in individuals suspected of having Lynch syndrome or colorectal cancer with clinical features of Lynch syndrome (PMID: 25980754, 31992580), in individuals with ovarian cancer (PMID: 33881185) and oligodendroglioma (PMID: 35982947). This variant has been identified in 1/244282 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Different variants affecting the same splice donor site, c..251-2A>G and c.251-2A>C, are known to be disease-causing (ClinVar variation ID: 91345, 233781). Loss of PMS2 function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Pathogenic. -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Jan 31, 2023	This variant causes an A to T nucleotide substitution at the -2 position of intron 3 of the PMS2 gene. Splice site prediction tools predict that this variant may have a significant impact on RNA splicing. Although this prediction has not been confirmed in published RNA studies, this variant is expected to result in an absent or disrupted protein product. This variant has been reported in individuals suspected of having Lynch syndrome or colorectal cancer with clinical features of Lynch syndrome (PMID: 25980754, 31992580), in individuals with ovarian cancer (PMID: 33881185) and oligodendroglioma (PMID: 35982947). This variant has been identified in 1/244282 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Different variants affecting the same splice donor site (c..251-2A>G, c.251-2A>C) are known to be disease-causing (ClinVar variation ID: 91345, 233781). Loss of PMS2 function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Jan 28, 2022	The c.251-2A>T intronic pathogenic mutation results from an A to T substitution two nucleotides before coding exon 4 in the PMS2 gene. This alteration was identified in a cohort of 1260 individuals undergoing panel testing for Lynch syndrome due to having a diagnosis of a Lynch-associated cancer and/or polyps (Yurgelun MB et al. Gastroenterology. 2015 Sep;149:604-13.e20). This alteration has also been identified in an individual diagnosed with colorectal cancer at 54. Immunohistochemistry of the tumor showed loss of expression of MSH6 and PMS2 (Wang Q et al. J Med Genet, 2020 07;57:487-499). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Two other alterations at this position (c.251-2A>G and c.251-2A>C) have been reported as pathogenic in Lynch syndrome and CMMR-D cohorts (Senter L et al. Gastroenterology. 2008 Aug;135:419-28; Niessen RC et al. Genes Chromosomes Cancer. 2009 Apr;48:322-9). 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. As such, this alteration is classified as a disease-causing mutation. -

Breast and/or ovarian cancer Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario

Jul 28, 2021

- -

Lynch syndrome 4;C5399763:Mismatch repair cancer syndrome 1 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Oct 31, 2018

- -

Hereditary nonpolyposis colon cancer Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jun 22, 2020

Variant summary: PMS2 c.251-2A>T is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Several computational tools predict a significant impact on normal splicing: Four predict the variant abolishes a 3' acceptor site. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 4.1e-06 in 244282 control chromosomes (gnomAD). c.251-2A>T has been reported in the literature in individuals affected with Hereditary Nonpolyposis Colorectal Cancer (e.g. Yurgelun_2015). These data indicate that the variant is likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Eight ClinVar submitters (evaluation after 2014) cite the variant as pathogenic/likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Hereditary nonpolyposis colorectal neoplasms Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Jan 18, 2024

This sequence change affects an acceptor splice site in intron 3 of the PMS2 gene. RNA analysis indicates that disruption of this splice site induces altered splicing and may result in an absent or disrupted protein product. This variant is present in population databases (rs587779340, gnomAD 0.0009%). Disruption of this splice site has been observed in individuals with constitutional mismatch repair deficiency syndrome and/or Lynch syndrome (PMID: 18602922, 21376568, 25980754). ClinVar contains an entry for this variant (Variation ID: 183893). Studies have shown that disruption of this splice site results in skipping of exon 4 and introduces a premature termination codon (Invitae). The resulting mRNA is expected to undergo nonsense-mediated decay. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.36
CADD	Pathogenic	31
DANN	Uncertain	0.99
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.94
FATHMM_MKL	Pathogenic	0.99	D
MutationTaster	Benign	1.0	D;D;D;D;D
GERP RS		5.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.73		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.73		Position offset: -2

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

Publications

LitVar

Other links and lift over

dbSNP: rs587779340; hg19: chr7-6043425;