The-174 G/C polymorphism of the interleukin-6 gene promoter and essential hypertension in an elderly Italian poppulation

Several studies have proposed a relationship between blood pressure and inflammation. Interleukin-6 (IL-6) is a multifunctional cytokine involved in inflammation and tissue injury and potentially influencing blood pressure. Recently, a common polymorphism of the IL-6 gene, associated with differences in the transcription rate of the protein, has been described. The aim of this study was to investigate a possible association between genetic variations of the -174GC polymorphism of the IL-6 gene promoter and hypertension in humans. IL-6 gene promoter polymorphism was evaluated by polymerase chain reaction followed by restriction enzyme analysis in 210 elderly Italian patients affected by essential hypertension (EH) and 177 age- and sex-matched controls. The distribution of IL-6 genotypes was 85 GG, 88 GC, 37 CC in the hypertensive patients and 65 GG, 73 GC, 39 CC in the control subjects. In this elderly cohort, no statistically significant association was found between the two groups (P = 0.45 for GG homozygous, P = 0.89 for GC heterozygous and P = 0.27 for CC homozygous). In conclusion the -174 GC polymorphism of the IL-6 gene promoter is not a marker for EH in this sample of elderly Italians.