Association of apolipoprotein A5 gene 1131T/C polymorphism with dyslipidemia and insulin resistance in Egyptian patients with metabolic syndrome

Metabolic syndrome (MetS) is a cluster of the most dangerous risk factors for type 2 diabetes mellitus and cardiovascular disease. The 1131T/C polymorphism of the apolipoprotein A5 (ApoA5) gene is associated with hypertriglyceridemia and correlates with impaired glucose homeostasis. These observations prompted us to explore the frequency of ApoA5 1131T/C polymorphism among patients with MetS as to assess its effects on lipid metabolism and insulin resistance. The study was conducted on 90 subjects divided into two groups: 60 MetS patients and 30 healthy controls. Fasting glucose, lipid profile, C-peptide (ELISA), and ApoA5 1131T/C polymorphism (PCR-RFLP) were done to all participants. CC genotype of ApoA5 gene was present only in MetS group compared to controls with a frequency of 13.3 vs. 0 % (P = 0.011), while the wild genotype (TT) was more frequent among the controls (86.7 vs. 56.7 %, P = 0.011). The mutant genotypes (TC, CC) were associated with higher risk for MetS (OR 4.97, 95 % CI = 1.5-16). The C allele was significantly increased in cases compared to controls (28.3 vs. 6.7 %, P = 0.001) and was associated with increased risk of MetS (OR = 5.535, 95 % CI = 1.8-16.4). Cholesterol, triglycerides, glucose levels, and modified HOMA-IR showed significantly higher values among TC/CC genotype carriers compared to TT genotype carriers, while HDL showed significantly lower values in the TC/CC genotype carriers compared to TT genotype carriers among MetS patients. Our findings show that ApoA5 gene 1131T/C polymorphism is associated with higher risk for MetS, and that the C allele carriers are more susceptible to dyslipidemia and insulin resistance. © 2012 Springer-Verlag London Limited.