Sex-specific interaction between APOE and APOA5 variants and determination of plasma lipid levels.

The APOA5 and APOE genes play an important role in determination of plasma levels of triglycerides (TG) and total cholesterol (TC). We have analyzed APOA5 (T-1131>C and Ser19>Trp) and APOE (e2/e3/e4) variants in 2500 representatively selected Caucasians (1168 men, 1332 women). In female subjects (but not in male) an association between APOE polymorphism and TC was observed on the background of the common APOA5 haplotype (TT-1131/SerSer19) - APOE2 carriers have the lowest (5.12 (1.15) mmol/l) and the APOE4 carriers have the highest (6.05 (1.06) mmol/l) levels of plasma TC (P<0.001). If at least one APOA5 C-1131 or Trp19 allele was present, APOE exhibits no significant effect on plasma TC. APOA5 did not affect plasma TG levels, if APOE4 allele was present. In the presence of APOE2 or APOE3, carriers of the APOA5 alleles, C-1131 and/or Trp19, have higher TG levels (1.64 (1.05) mmol/l) than others (1.37 (0.75) mmol/l) (P<0.01). In male subjects, the same, but non-significant trend was observed. In female subjects, we have detected an interaction between APOE and APOA5 variants and plasma lipid levels.