Although the genetic heterozygosity of the rs11171806 characterized in this study was too low to be useful for susceptibility analysis to MS or other IDD disease, three variants (rs2066808, rs2371494, rs11575248) within the 5-‘UTR or near the 3-‘UTR of the IL-23A gene were significantly associated with the risk of MS or other IDD, providing opportunities for etiological and pathogenesis studies. Here, IL23A is linked to myeloid sarcoma.