 Individually, neither apo A1 nor apo E was found to be associated with triglyceride (TG) levels, but pairwise epistasis (additive x additive model) explored their significant synergistic contributions with raised TG levels (P<0.01).Apo A1 production is decreased by calcitriol, and increased by a drug that antagonizes it.Exercise or statin treatment may cause an increase in HDL-C levels by inducing apo A1 production, but this depends on the G/A promoter polymorphism.