Specifically, the combination of the risk alleles of IRAK-1 rs3027898 (C allele) and miR-146a rs2910164 (G allele) was associated with an increased MS risk, whereas the interaction of the protective alleles of IRAK-1 rs3027898 (A allele) and miR-146a rs57095329 (G allele) conferred protection against SPMS. The gene discussed is IRAK1; the disease is secondary progressive multiple sclerosis.