The Association of IL-6, TNFα and CRP Gene Polymorphisms with Coronary Artery Disease in a Tunisian Population: A Case–Control study

Coronary artery disease is an inflammatory disease. Systemic markers of inflammation such as Interleukin-6, Tumor Necrosis Factor alpha and C-reactive protein have previously been shown to be associated with increased risk of cardiovascular events. The aim of the present study is to assess the role of variants in the IL-6 (− 174 G/C), TNFα (− 308 A/G) and CRP (+ 1059G/C) genes as susceptibility markers for CAD in a Tunisian population. The investigation was conducted as a case–control study involving 204 patients and 400 age-gender matched controls. Genotyping was performed using polymerase chain reaction and restriction fragment length polymorphism analysis. There are significant differences between CAD patients and the control group with regard to BMI (p < 10–3) and family history of CAD (p < 10–3). The CAD patients are more likely to have a history of smoking (p < 10–3), have a higher value of TC (p = 0.003), LDLc (p = 0.016), hs-CRP (p = 0.01), IL6 (p < 10–3) and TNFα (p = 0.038). Our analysis showed significant differences between cases and controls in genotypic distribution of IL6-174CC (p = 0.003; OR = 7.71 CI (1.58–37.56)), TNFα − 308 AA (p = 0.004; OR = 2.95 (1.57–5.51)) and CRP + 1059 CC (p < 10–3; OR = 5.40 (2.30–12.68)). However, we failed to find an association between the different genotypes and the inflammatory markers levels. Our results suggest that the presence of IL-6 (− 174 G/C), TNFα (-308 A/G) and CRP (+ 1059G/C) polymorphisms, may be considered to be a risk factor for CAD in Tunisian population.