Lack of Association between Interleukin 12 C(-1188)A Polymorphism and Irritable Bowel Syndrome.

Irritable Bowel Syndrome (IBS) is a functional gastrointestinal disorder, characterized by recurrent abdominal pain and altered bowel habits. This study was performed to investigate the important role of interleukin-12 (IL-12) in intestinal inflammation. For this study seventy one patients with IBS and 140 controls were investigated. The allele and genotype frequencies of IL-12 C(-1188)A were determined using polymerase chain reaction with sequence-specific primers. The allele A was more common that the allele C in both groups of patients and controls. There was not any significant difference on IL-12 alleles and genotypes between patients and controls. The AA genotype was the most common genotypes, which was seen in 57.4% of the patients and 51.4% of the controls (p = 0.53). Although frequency of the CC genotype in the control group was lower than the patient group, this difference was not significant (5.7% vs. 11.5%, respectively, p = 0.16). Considering the lack of association between IL-12 C(-1188)A polymorphism and IBS, this cytokine gene polymorphism may not have significant role in the pathophysiology of disease.