Inflammatory bowel disease (IBD) with ulcerative colitis (UC) and Crohn's disease (CD) as the most common forms is an inflammation of the gastrointestinal tract. Familial Mediterranean fever (FMF) is another inflammatory disease as well. In the current study we studied FMF gene mutations in 47 patients with IBD and 25 healthy individuals to investigate the effects of these mutations on the clinical status of IBD. Twelve mutations were analyzed by reverse hybridization after multiplex PCR amplification of DNA samples. We did not find an association between FMF gene mutations and IBD phenotypic characteristics. However, in patients without Mediterranean fever (MEFV) mutations, extraintestinal disease frequencies were higher (p<0.05). IBD has a genetic basis with multiple genes probably playing a role via several pathways during disease progression. Studying other genes interacting with FMF gene in a larger group of patients will add to the knowledge of disease pathogenesis.