Proprotein Convertase Subtilisin/Kexin Type 9 Gene E670G Polymorphism Interacts with Alcohol Consumption to Modulate Serum Lipid Levels

Backgroud: Both alcohol consumption and the proprotein convertase subtilisin/kexin type 9 (PCSK9) gene polymorphism modulate serum lipid levels, but their interactions on serum lipid profiles are still unknown. The present study was undertaken to detect the interactions of PCSK9 E670G polymorphism and alcohol consumption on serum lipid levels. Methods: Genotypes of the PCSK9 E670G in 1352 unrelated subjects (785 non-drinkers and 567 drinkers) were determined by polymerase chain reaction and restriction fragment length polymorphism combined with gel electrophoresis, and then confirmed by direct sequencing. The interactions between PCSK9 E670G genotypes and alcohol consumption on serum lipid parameters were detected by using a factorial design covariance analysis after controlling for potential confounders. Results: The levels of serum triglyceride, high-density lipoprotein cholesterol, apolipoprotein (Apo) A1, and the ratio of ApoA1 to ApoB were higher in drinkers than in non-drinkers (P < 0.01 for all), whereas the levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and ApoB were lower in drinkers than in non-drinkers (P < 0.001 for all). The genotypic and allelic frequencies of PCSK9 E670G were not different between non-drinkers and drinkers (P > 0.05 for each). The subjects with AA genotype in non-drinkers had higher serum LDL-C levels than the subjects with AG genotype, whereas the subjects with AG genotype in drinkers had higher serum TC levels than the subjects with AA genotypes (P < 0.05 for each). The effects of alcohol consumption on TC and LDL-C levels depended upon genotypes, the subjects with AA genotype had lower serum TC and LDL-C levels in drinkers than in non-drinkers. Conclusions: Alcohol consumption can modify the effects of the PCSK9 E670G polymorphism on serum TC and LDL-C levels. The subjects with AA genotype of the PCSK9 E670G benefit more from alcohol consumption than the subjects with AG genotype in decreasing serum TC and LDL-C levels.