Genome-wide array analysis of Iranian patients with BD and controls identified an association with five coding polymorphisms of the gene encoding fucosyltransferase -2 (FUT2), including the rs601338 nonsense variant which, in Caucasians, determines the secretion of the H antigen (precursor of the ABO blood group antigens) in body fluids and on the intestinal mucosa. The gene discussed is FUT2; the disease is Behcet disease.