Submissions for variant NM_005084.4(PLA2G7):c.663+1G>A

gnomAD frequency: 0.00001  dbSNP: rs201899866

Total submissions: 3

Submitter	RCV	SCV	Clinical significance	Condition	Last evaluated	Review status	Method	Comment
Women's Health and Genetics/Laboratory Corporation of America, LabCorp	RCV002265809	SCV002548359	uncertain significance	not specified	2022-05-01	criteria provided, single submitter	clinical testing	Variant summary: PLA2G7 c.663+1G>A alters a conserved nucleotide 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 the canonical 5' splicing donor site. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 0.00096 in 251324 control chromosomes in the gnomAD database, including 3 homozygotes. This frequency does not allow conclusions about variant significance. c.663+1G>A has been reported in the literature in individuals affected with Lipoprotein-associated phospholipase A2 (Lp-PLA2) Deficiency, an enzyme that hydrolyzes phospholipids to generate lysophosphatidylcholine and oxidized nonesterified fatty acids (example, Salaheen_2017). In observational epidemiologic studies, higher soluble Lp-PLA2 enzymatic activity has been correlated with increased risk for coronary heart disease; small molecule inhibitors of Lp-PLA2 have been developed for the treatment of coronary heart disease (Salaheen_2017 citing Di Angelantonio_2012). This study identified participants who are naturally deficient in the Lp-PLA2 enzyme including two homozygotes and 106 heterozygotes. A dose-dependent response relationship between genotype and enzymatic activity was observed, however, carriers of c.663+1G>A did not have a reduced risk of myocardial infarction (Salaheen_2017). These report(s) do not provide unequivocal conclusions about association of the variant with Platelet-Activating Factor Acetylhydrolase Deficiency and an associated risk for myocardial infarction and/or stroke. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. One clinical diagnostic laboratory and the OMIM database have submitted clinical-significance assessments for this variant to ClinVar after 2014. The clinical diagnostic laboratory classified the variant as a risk factor for coronary heart disease citing overlapping evidence utilized in the context of this evaluation. Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic.
OMIM	RCV000578126	SCV000679983	pathogenic	Platelet-activating factor acetylhydrolase deficiency	2018-01-24	no assertion criteria provided	literature only
Reproductive Health Research and Development, BGI Genomics	RCV000578126	SCV001142359	risk factor	Platelet-activating factor acetylhydrolase deficiency	2020-01-06	no assertion criteria provided	curation	NG_016204.1(NM_001168357.1):c.663+1G>A in the PLA2G7 gene has an allele frequency of 0.008 in South Asian subpopulation in the gnomAD database, including three homozygotes. The c.663+1G>A variant destroys the canonical splice donor site in intron 13. It is predicted to cause abnormal gene splicing, either leading to an abnormal message that is subject to nonsense-mediated mRNA decay or to an abnormal protein product if the message is used for protein translation. However, activity of soluble lipoprotein-associated phospholipase A2 (encoded by PLA2G7) has been correlated with risk for coronary heart disease (PMID: 28406212). Taken together, we interprete this variant as risk factor variant.