Although the relationships between NKG2D and MICA polymorphisms associated with autoimmune and neoplastic diseases, including ankylosing spondylitis [7], Behçet's disease [8], psoriasis vulgaris [9], and Kawasaki's disease [10], have been defined, this is not the case for the association of MICA alleles with AITD. This evidence concerns the gene MICA and ankylosing spondylitis.