Background: Apolipoprotein A5 (APOA5) gene polymorphisms are usually associated with plasma triglyceride levels. We evaluated the relationship of the APOA5 -1131T>C and c.56C>G polymorphisms [single nucleotide polymorphism (SNP)] with serum lipids, dyslipidemia [low high-density lipoprotein (HDL)/high triglyceride] and the risk for metabolic syndrome (MS) in the Turkish Adult Risk Factor study.
Methods: We genotyped SNPs using the Taqman allelic discrimination assays in 1564 Turkish adults (51.4% female, mean age 54.1+/-11.6 years). MS and dyslipidemia were defined using the criteria of the National Cholesterol Education Program.
Results: For both SNPs, rare allele carriers had significantly higher fasting triglyceride levels in both genders, except the c.56G allele in men. The -1131C allele was associated with lower HDL cholesterol (HDL-C) levels in women. In relation to dyslipidemia, the c.56C>G and haplotype 1 had significant gender-genotype interactions (p<0.05). Otherwise, both SNPs were significantly associated with dyslipidemia after adjustment for risk factors in women. After similar adjustment, non-carriers of the haplotype 1 (odds ratio=4.1, p=0.003) increased the MS risk in women. However, no significant associations emerged between SNPs and HDL-C, dyslipidemia or MS in a similar analysis in men.
Conclusions: Excess risk for low HDL-C, dyslipidemia and MS is associated with the rare alleles of the APOA5 SNPs and non-carriers of common haplotype in women.