Functional associations between the SNPs and the phenotypes.

The figure depicted the biological functional associations between four SNPs and different traits of MetS. KCNQ1 (potassium voltage-gated channel KQT-like subfamily, member 1) is a gene encoding the poreforming subunit of a voltage-gated K+ channel (KvLQT1) that plays a key role for the repolarization of the cardiac action potential as well as water and salt transport in the beta cells. T allele variant might inhibit the KV-channels in beta cells and enhance glucose-stimulated insulin secretion, which leads to an increased risk of diabetes. ACE gene encoding the angiotensin (Ang) and transform Ang I into Ang II, and the activation of Ang IImight increase the storage of TG by influencing the glycolysis process and lead to the adipocyte hypertrophy. C allele variant of the INSIG2 gene was involved in the reversed cholesterol transport by an interaction with sterol regulatory element-binding proteins (SREBPs), which are transcription factors that activate the synthesis of cholesterol and fatty acids in the liver and other organs. In addition, A to C transition at nucleotide 1298 (A1298C, rs1801131) of the coding sequence in gene MTHFR, have been shown to be the most frequent genetic causes for mild hyperhomocysteinemia, and a high plasma concentration of homocysteine may predispose to atherosclerosis by injuring the vascular endothelium, which might result in hypertension.