Significant risk associations with HAM/TSP (P < 2.02 × 10−4) were observed for HLA-C*07:02 (P = 2.61 × 10−5), HLA-B*07:02 (P = 4.97 × 10−10), HLA-DRB1*01:01 (P = 1.15 × 10−9), and HLA-DQB1*05:01 (P = 2.30 × 10−9) (Table 2 and SI Appendix, Table S2). This evidence concerns the gene HLA-DQB1 and tropical spastic paraparesis.