We found that three variants (rs2066808, rs2371494, rs11575248) in the IL-23A gene and one variant (rs1884444) in the IL-23R gene were associated with the risk of IDD, especially MS; the serum levels of IL23A in the MS patients were altered by the co-effects of the variants. The gene discussed is IL23R; the disease is intervertebral disk degenerative disorder.