ankylosing spondylitis being over 100. The corresponding χ2 values were nearly all at least 15, and many were much greater. The exceptions to high ORs were those for multiple sclerosis (OR = 1.7), acute lymphatic leukemia (OR = 1.7) and Hodgkin's disease (ORs = 1.3–1.7). The multiple sclerosis association became stronger with the discovery of the HLA class II antigens, and later data suggested an OR of about 2 for the association between Hodgkin's disease and HLA-DP13.
