Objective: To investigate the effects of lipoprotein lipase gene (LPL) Ser447stop polymorphism on serum lipid ratios and their responses to high-carbohydrate/low-fat (HC/LF) diet in healthy youth.
Methods: Fifty-six healthy subjects [(22.89 +/- 1.80) years) were given control diets of 31% fat and 54% carbohydrate for 7 days, followed by HC diets of 15% fat and 70% carbohydrate for 6 days, without total energy restriction. Serum lipid profiles at baseline, before and after HC diets, as well as LPL Ser447stop polymorphisms were analyzed. TG/ HDL-C, log (TG/HDL-C), TC/HDL-C, and LDL-C/HDL-C were calculated.
Results: No significant differences were found of the lipid ratios at baseline and before and after HC/LF diet between subjects of wild type (S447S) and mutation carriers (447XC) in the whole study population or males and females separately. When compared with those before HC/LF diet, significantly decreased LDL-C/HDL-C and TC/HDL-C were found regardless of LPL Ser447stop genotype (P < 0.05) and increased log (TG/HDL-C) in subjects with S447S (P < 0.05) in the whole study population. After gender was taken into account, LDL-C/HDL-C and TC/HDL-C were significantly decreased in males (P < 0.001) regardless of LPL Ser447stop polymorphism. TG/HDL-C and log (TG/HDL-C) were significantly increased (P < 0.05), and LDL-C/HDL-C and TC/HDL-C were significantly decreased (P < 0.05) in females with S447S. No significant differences were found in females with 447XC.
Conclusion: The functional C to G mutation of LPL Ser447Stop could attenuate the elevated log (TG/HDL-C) induced by HC/LF diet. Interactions of LPL Ser447Stop polymorphism with HC/LF diet on the lipid ratios were gender-specific and effective only in females.