Influence of the −308 TNF-α and −174 IL-6 polymorphisms on lipid profile in Mexican subjects

Abstract

Polymorphisms in the promoter region of several cytokine genes have been associated with differential cytokine production. Several reports indicate that polymorphisms in the tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) genes are associated with lipid abnormalities. The aim of this study was to identify the genotype frequencies for -308G/ATNF-alpha and -174G/CIL-6 polymorphisms in Mexican subjects and to determine the influence of both polymorphisms on serum lipid levels. Serum lipid concentrations were measured in 100 healthy Mexican subjects. Screening of the -308G/ATNF-alpha and -174G/CIL-6 polymorphisms was performed in all participants using PCR-RFLPs. Genotype frequency for TNF-alpha polymorphism was: 87% GG and 13% GA, whereas IL-6 polymorphism was: 77% GG and 23% GC. The polymorphism frequencies obtained in this study were significantly different to Caucasian populations. High serum levels of triglycerides and total cholesterol were associated with GG genotype of the -308 TNF-alpha polymorphism, as well as low HDL-c levels, but no association was found between the -174 IL-6 polymorphism and serum lipid concentrations. We observed a significant association of the -308 TNF-alpha polymorphism with lipid profile in Mexican subjects. Furthermore, the genotype distribution of -308 TNF-alpha and -174 IL-6 polymorphisms in Mexican Mestizo population similar to populations in different continents may be due to our genetic background influenced by the mixture of Spaniards, Indian and black genes.