ClinVar Genomic variation as it relates to human health

MAF >1%

Converted during submission to Benign.

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. The evidence from the literature, in combination with allele frequency data from public databases where available, was sufficient to determine this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign.

This alteration is classified as benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity.

This variant is considered benign. This variant is a silent/synonymous amino acid change and it is not expected to impact splicing.

The PMS2 p.His496= variant was identified in the literature, although the frequency of this variant in an affected population was not provided. The variant was identified in dbSNP (rs1805320) as “with benign allele” and ClinVar (classified as benign by Ambry Genetics, Color, Invitae, Counsyl and 6 other submitters; and as likely benign by True Health Diagnostics and Illumina). The variant was identified in control databases in 2168 of 282,774 chromosomes (70 homozygous) at a frequency of 0.008, increasing the likelihood this could be a low frequency benign variant (Genome Aggregation Database Feb 27, 2017). The variant was observed in the following populations: African in 1934 of 24,924 chromosomes (freq: 0.08), Latino in 163 of 35,440 chromosomes (freq: 0.005), Other in 22 of 7220 chromosomes (freq: 0.003), South Asian in 10 of 30,616 chromosomes (freq: 0.0003), European in 36 of 129,170 chromosomes (freq: 0.0003), Ashkenazi Jewish in 1 of 10,368 chromosomes (freq: 0.0001), East Asian in 1 of 19,946 chromosomes (freq: 0.00005), and Finnish in 1 of 25,090 chromosomes (freq: 0.00004). The variant was observed with a co-occurring, pathogenic PMS2 variant (p.SerGlyfs*3) in an individual with colorectal cancer (Nomura 2015), decreasing the likelihood that this variant has clinical significance. The p.His496= variant is not expected to have clinical significance because it does not result in a change of amino acid and is not located in a known consensus splice site. The variant occurs at a non-highly conserved nucleotide outside of the splicing consensus sequence and in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a difference in splicing. In summary, based on the above information, this variant meets our laboratory's criteria to be classified as benign.