7-5995614-G-C
Variant summary
Our verdict is Uncertain significance. Variant got 1 ACMG points: 1P and 0B. PP3
The NM_000535.7(PMS2):āc.823C>Gā(p.Gln275Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000273 in 1,612,770 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/23 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Q275H) has been classified as Uncertain significance.
Frequency
Consequence
NM_000535.7 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Uncertain_significance. Variant got 1 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000329 AC: 5AN: 152192Hom.: 0 Cov.: 32
GnomAD3 exomes AF: 0.0000796 AC: 20AN: 251410Hom.: 0 AF XY: 0.0000883 AC XY: 12AN XY: 135874
GnomAD4 exome AF: 0.0000267 AC: 39AN: 1460578Hom.: 0 Cov.: 30 AF XY: 0.0000289 AC XY: 21AN XY: 726680
GnomAD4 genome AF: 0.0000329 AC: 5AN: 152192Hom.: 0 Cov.: 32 AF XY: 0.0000404 AC XY: 3AN XY: 74330
ClinVar
Submissions by phenotype
Lynch syndrome 4 Uncertain:3
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This variant is classified as a variant of uncertain significance as there is insufficient evidence to determine its impact on protein function and/or cancer risk. -
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Hereditary cancer-predisposing syndrome Uncertain:2
This missense variant replaces glutamine with glutamic acid at codon 275 of the PMS2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). Splice site prediction tools suggest that this variant may impact RNA splicing, and a minigene assay has shown that this variant causes abnormal RNA splicing and creates two aberrant transcripts (PMID: 26247049). However, this observation has not been confirmed using RNA from carriers. This variant has not been reported in an individual affected with a PMS2-related disorder in the literature. This variant has been identified in 23/282824 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The 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. -
The p.Q275E variant (also known as c.823C>G), located in coding exon 8 of the PMS2 gene, results from a C to G substitution at nucleotide position 823. The glutamine at codon 275 is replaced by glutamic acid, an amino acid with highly similar properties. In one study, the effect of the c.823C>G variant on splicing was analyzed using a minigene assay which generated two aberrant transcripts due to the use of a cryptic splice acceptor site that was stronger than the canonical splice site; however, patient RNA was not available for direct analysis (van der Klift HM et al. Mol Genet Genomic Med. 2015 Jul;3:327-45). In silico splice site analysis predicts that this alteration will result in the creation or strengthening of a novel splice acceptor site. RNA studies have demonstrated that this alteration results in an incomplete splice defect; the clinical impact of this abnormal splicing is unknown at this time (Ambry internal data). This nucleotide position is not well conserved in available vertebrate species. This amino acid position is poorly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -
not specified Uncertain:1
Variant summary: PMS2 c.823C>G (p.Gln275Glu) results in a conservative amino acid change located in the DNA mismatch repair protein family, N-terminal domain of the encoded protein sequence. Five of five in-silico tools predict a benign effect of the variant on protein function. Several computational tools predict a significant impact on normal splicing: Two predict the variant creates an alternative 3 prime acceptor site. At least one publication reports experimental evidence that this variant affects mRNA splicing (van der Klift_2015). The variant allele was found at a frequency of 8e-05 in 251410 control chromosomes. The observed variant frequency is slightly higher than the estimated maximal expected allele frequency for a pathogenic variant in PMS2 causing Hereditary Nonpolyposis Colorectal Cancer phenotype (7.1e-05), suggesting that the variant is benign. To our knowledge, no occurrence of c.823C>G in individuals affected with Hereditary Nonpolyposis Colorectal Cancer has been reported. Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation (likely benign n=1, VUS n=4). Based on the evidence outlined above, the variant was classified as uncertain significance. -
Lynch syndrome Uncertain:1
This missense variant replaces glutamine with glutamic acid at codon 275 of the PMS2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). Splice site prediction tools are inconclusive regarding the impact of this variant on RNA splicing. A minigene assay has shown that this variant causes abnormal RNA splicing and creates two aberrant transcripts (PMID: 26247049). However, this observation has not been confirmed using RNA from carriers. This variant has been reported in an individual affected with a PMS2-related disorder (Color internal data). This variant has been identified in 23/282824 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The 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. -
not provided Uncertain:1
Observed in a patient with a personal and/or family history suggestive of Lynch syndrome (PMID: 26247049); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; In silico analysis indicates that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 11574484, 26247049) -
Hereditary nonpolyposis colorectal neoplasms Benign:1
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Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at