Interleukin-6 gene promoter polymorphisms and cardiovascular risk factors. A family study

Interleukin-6 (IL-6) is a cytokine involved in inflammatory process, as well as in glucose and lipid metabolism. Several studies of the biological relevance of IL-6 gene polymorphisms have indicated a relationship with cardiovascular disease. The aim of this study was to assess whether the -174 G/C and -572 G/C of IL-6 gene polymorphisms are associated with cardiovascular risk factors in Mexican families. Ninety members of 30 Mexican families, in which an index case (proband) had obesity, were included in the study. We evaluated the body composition by bioelectrical impedance. Peripheral blood samples were collected to determine biochemical and hematological parameters. High sensitivity C-reactive protein levels were measurement for nephelometric analysis. Screening for both polymorphisms studied was performed by PCR-RFLP. In the parents, both polymorphisms were in Hardy-Weinberg's equilibrium. The genotypes -174 GC/CC were associated with T2D (OR = 1.23, IC 95% 1.01-1.5) and highest levels of hsCRP (p = 0.02), whereas genotype -572 GG was associated with T2D (OR = 1.24, IC 95% 1.04-1.47) with an inflammatory state determined by the increase in the leukocyte count (OR = 1.24, IC 95% 1.02-1.51). The genotypes -174 GC/CC and -572 GG may confer susceptibility for the development of subclinical inflammation and type 2 diabetes in Mexican families.