Interplays of Dietary Fat with BMI and FAAH rs324420 on HDL-C in Gender-Dependent Manner in Adolescents

The present study was to explore relationship between serum lipid profiles and the polymorphism of rs324420 at fatty acid amide hydrolase (FAAH) gene (FAAH rs324420) and its confounders in Chinese adolescents. Serum lipids, glucose, and insulin levels were assessed using routine methods in a cohort of 708 high school students. Dietary intake was investigated by 3-day diet records, and intakes of protein, fat, and carbohydrate were calculated. FAAH rs324420 was genotyped by polymerase chain reaction-restriction fragment length polymorphism technique and confirmed through DNA sequencing. In the whole study population, increased HDL-C levels were observed in FAAH rs324420 CC homozygotes than those in A allele carriers. Body mass index (BMI), gender, intake of fat, and FAAH rs324420 were predictive factors of HDL-C levels in the whole study population. Moreover, BMI and intake of fat were predictors of HDL-C levels in male FAAH rs324420 A allele carriers and female CC homozygotes, but only BMI was predictor of HDL-C in female A allele carriers and male CC homozygotes. These results demonstrate that there are mutual effects of dietary fat with gender, BMI, and FAAH rs324420 on HDL-C levels, which pave a novel way to explore the heterogeneous relationship of serum lipid profiles with diets or FAAH rs324420 and provide a new perspective of precision dietary interventions of dyslipidemia, especially in adolescents.