Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong
The NM_000535.7(PMS2):c.1144+3A>G variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,610,368 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).
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]
Uncertain significance, criteria provided, single submitter
clinical testing
Labcorp Genetics (formerly Invitae), Labcorp
Mar 25, 2022
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. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. ClinVar contains an entry for this variant (Variation ID: 1002570). This variant has not been reported in the literature in individuals affected with PMS2-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.007%). This sequence change falls in intron 10 of the PMS2 gene. It does not directly change the encoded amino acid sequence of the PMS2 protein. It affects a nucleotide within the consensus splice site. -
Uncertain significance, criteria provided, single submitter
clinical testing
Ambry Genetics
Oct 09, 2020
The c.1144+3A>G intronic variant results from an A to G substitution 3 nucleotides after coding exon 10 in the PMS2 gene. This nucleotide position is not well conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will not have any significant effect on splicing. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -