Frequency of three common mutations of CARD15/NOD2 gene in Iranian IBD patients.

BACKGROUND The CARD15/NOD2 gene, located on the pericentromeric region of chromosome 16 (IBD1) has been reported to have an association with IBD, especially Crohn's disease. Three common mutations of CARD15 are variably associated with Crohn's disease in different ethnic groups. We evaluated the frequency of these mutations (R702W, G908R and 1007fsinsC) in Iranian IBD patients and compared it with the healthy control population. METHODS One hundred patients with ulcerative colitis, 40 patients with Crohn's disease, and 100 sex- and age-matched controls were enrolled from a tertiary center during a one-year period (2005-2006). The three mutations were assessed in DNA of leukocytes by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). RESULTS The frequency of R702W mutation was significantly higher in Iranian patients with Crohn's disease (p< 0.001; OR 19.21; 95% CI 4.23-87.32) compared to healthy controls. No association was observed between the other mutations and Crohn's disease and none of these mutations was associated with ulcerative colitis. CONCLUSION The R702W mutation of CARD15 gene was associated with Crohn's disease in the Iranian population.