Abstract: Genetic Background: Behcet’s Disease (BD) is known t0 be associated with the HLA-B5 gene. The association is with the B51subtype, the B*5101allele. The tryptophan amino acid in position 167 and histidine in position 171 seems to determine the susceptibility of B51 for BD. However all persons with B51 do not have BD and all BD patients do not have B51. Some particularity in the TNFβ gene region in BD patients ...