TNF and Crohn disease: Variants controlling TNF-α levels are associated with a range of autoimmune diseases such as psoriasis, rheumatoid arthritis, and Crohn disease in which the role of TNF-α is known (Baurecht et al., 2015, Dunstan et al., 2014, Freudenberg et al., 2011, Yamazaki et al., 2013), and also with Kashin-Beck disease, corroborating its suspected inflammatory nature (Zhang et al., 2015a).