Of all the Th17 pathway genes, the interleukin 23 receptor (IL23R) gene (GenBank accession: NM_144701, GeneID: 149233) on chromosome 1p31 confers the highest odds-ratio (OR) for disease development/lowest OR for disease protection [4], [5], [6], [7], [8], [9], [10], [11], [12], as well as being implicated in other chronic inflammatory diseases including psoriasis [13] and ankylosing spondylitis [14]. Here, IL23R is linked to ankylosing spondylitis.