Integrative mutation, haplotype and G × G interaction evidence connects ABGL4, LRP8 and PCSK9 genes to cardiometabolic risk

This study is expected to investigate the association of ATP/GTP binding protein-like 4 (AGBL4), LDL receptor related protein 8 (LRP8) and proprotein convertase subtilisin/kexin type 9 (PCSK9) gene single nucleotide variants (SNVs) with lipid metabolism in 2,552 individuals (Jing, 1,272 and Han, 1,280). We identified 12 mutations in this motif. The genotype and allele frequencies of these variants were different between the two populations. Multiple-locus linkage disequilibrium (LD) elucidated the detected sites are not statistically independent. Possible integrative haplotypes and gene-by-gene (G × G) interactions, comprising mutations of the AGBL4, LRP8 and PCSK9 associated with total cholesterol (TC, AGBL4 G-G-A, PCSK9 C-G-A-A and G-G-A-A-C-A-T-T-T-G-G-A), triglyceride (TG, AGBL4 G-G-A, LRP8 G-A-G-C-C, PCSK9 C-A-A-G, A-A-G-G-A-G-C-C-C-A-A-G and A-A-G-G-A-G-C-C-C-G-A-A), HDL cholesterol (HDL-C, AGBL4 A-A-G and A-A-G-A-A-G-T-C-C-A-A-G) and the apolipoprotein(Apo)A1/ApoB ratio (A1/B, PCSK9 C-A-A-G) in Jing minority. However, in the Hans, with TG (AGBL4 G-G-A, LRP8 G-A-G-C-C, PCSK9 C-A-A-G, A-A-G-G-A-G-C-C-C-A-A-G and A-A-G-G-A-G-C-C-C-G-A-A), HDL-C (LRP8 A-A-G-T-C), LDL-C (LRP8 A-A-G-T-C and A-A-G-A-A-G-T-C-C-A-A-G) and A1/B (LRP8 A-C-A-T-T and PCSK9 C-A-A-G). Association analysis based on haplotype clusters and G × G interactions probably increased power over single-locus tests especially for TG.