BACKGROUND AND OBJECTIVESThe tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-6 gene polymorphism has a controversial role in the pathogenesis of cardiovascular disease among different populations. The effect of the cytokine’s gene polymorphism on idiopathic dilated cardiomyopathy (IDCM) is still unresolved. The current study aimed to evaluate the association of the TNF-α −308 G/A and IL-6 −174 G/C polymorphism with IDCM in a Pakistani population.DESIGN AND SETTINGSBlood samples for this case-control study were collected from the cardiology outpatient department of multiple cardiology centers of Rawalpindi/Islamabad, Pakistan, between July 2012 and December 2012.PATIENTS AND METHODSIDCM cases (number [n]=250) and healthy controls (n=300) were genotyped using polymerase chain reaction and restriction fragment length polymorphism.RESULTSThe TNF-α −308 variant genotypes GA and AA were more prevalent in patients compared with the control group (P<.0001). Similarly, the IL-6 −174 variant genotypes GC and CC showed a high prevalence in patients with IDCM compared with healthy controls (P=.0019). IDCM cases had a higher prevalence of the TNF-α–308A (P<.0001) and the IL-6 −174C (P=.0008) mutant alleles than did the control group. The IDCM cases bearing the TNF-α−308 and IL-6 variant genotypes revealed elevated levels of high-sensitivity C-reactive protein (hs-CRP) when compared with the corresponding controls (P<.05).CONCLUSIONThe TNF-α −308 G/A and IL-6 −174 G/C gene polymorphisms and high levels of hs-CRP may be associated with the pathogenesis of IDCM in the study population.

Background. Tumor necrosis factor-alpha (TNF-α) gene polymorphisms have been implicated in the manifestation of atherosclerosis. Controversy exists regarding the link between the cytokine's variant genotype and CHD among different ethnic groups. There have been fewer studies on the TNF-α gene −1031T>C and −863C>A polymorphisms in relation to CHD. Therefore, the current study was designed to investigate the association of the TNF-α gene −1031T>C and −863C>A polymorphisms with CHD in a Pakistani population. Methods. Patients with CHD (n = 310) and healthy individuals (n = 310) were enrolled in this study. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results. A significant difference was observed in the −863C>A polymorphism between patients with CHD and control subjects (P < 0.0001). CHD risk was positively associated with the variant allele −863A (P < 0.0001) in the study subjects. There was no significant link between the −1031T>C polymorphism and CHD risk in the study population. Haplotypes A-T and A-C of the TNF-alpha gene loci at −863 and −1031 showed higher frequency in the patient group compared with controls (P < 0.05). Conclusion. The TNF-α  −863C>A gene polymorphism was associated with the pathogenesis of CHD while the −1031T>C polymorphism did not show any link with the disease in a Pakistani population.