In our study, possible haplotypes were determined by studying the polymorphisms of different loci for IL-12B (rs3213119, rs3213120, rs3212227, rs3213113, and rs2082412, respectively) and IL-23R (rs1004819, rs7517847, rs7530511, rs10489629 and rs10889677, respectively) which play a crucial role in immune regulation in BD. The gene discussed is IL12B; the disease is Behcet disease.