Apolipoprotein A5 gene -1131T/C polymorphism is associated with the risk of metabolic syndrome in ethnic Chinese in Taiwan

Background: The -1131T>C polymorphism in the apolipoprotein gene A5 (APOA5) was found to be associated with increased levels of plasma triglyceride and decreased levels of high-density lipoprotein cholesterol (HDL-C), which are characteristic dyslipidemic components of metabolic syndrome. This study aimed to identify a link between this polymorphism and the risk of metabolic syndrome. Methods: The sample population comprised 615 unrelated subjects, 18.7% of whom had metabolic syndrome. Genotypes were determined via polymerase chain reaction, restriction mapping with MseI, and gel electrophoresis. Results: A significantly higher level of triglycerides and a lower level of HDL-C were noted in carriers of the -1131C allele than in the non-carriers (p<0.001 and p=0.044, respectively). The frequency of the -1131C allele in the metabolic syndrome-affected subjects was significantly higher than that of the group of unaffected subjects (37.4% vs. 27.7%, p=0.004). Even after adjusting for age, gender, smoking, regular exercise, and waist-to-hip ratio, the APOA5 -1131C allele carriers remained significantly associated with an increased risk of metabolic syndrome (OR=1.77, 95% CI, 1.13-2.77; p=0.012). Conclusions: These results indicate that the association of APOA5 -1131T>C polymorphism with dyslipidemia can also contribute to an increased susceptibility to metabolic syndrome in the Chinese, as a result of its effect on triglyceride metabolism.