Further research utilizing genome-wide association studies demonstrated links between single-nucleotide polymorphisms in IL23p19 and IL23R and the incidence of ankylosing spondylitis, Crohn's disease (CD), ulcerative colitis (UC), and psoriasis among other disorders, identifying that IL-23 rather than IL-12 was involved in these diseases (Cargill et al., 2007; Dong et al., 2013; Duerr et al., 2006). The gene discussed is IL23A; the disease is psoriasis.