TLR4 and Arthritis: Polymorphisms within TLR4 have been associated with a number of autoimmune conditions, genetically linked to psoriasis, including Crohn disease [13], vitiligo [10] and ulcerative colitis [13] as well as a wide range of other diseases including Behcet’s involving arthritis [8], atherosclerosis [5] and endotoxin hyporesponsiveness [1].