Analysis of the detected MEFV mutations in the group of IBD patients with concomitant FMF (42 mutations in 25 patients) showed that the M694 mutation was the most frequent at 21 of 42 (50%), followed by the V726A mutation in 12 (28.5%), more rarely M680I in 4 (9.5%,), then E148Q in 2 (4.7%), R761H in 2 (4.7%), and, seldom, P369S in 1 (2.3%) (Table 8). The gene discussed is MEFV; the disease is inflammatory bowel disease.