Possession of the HLA-class I gene HLA-A*02 and Cw*08 was associated with a significant reduction in both HTLV-1 PVL and the risk of HAM/TSP (Jeffery et al., 1999, 2000; Catalan-Soares et al., 2009), while individuals with HLA-class I HLA-B*5401 and class II HLA-DRB1*0101 was indicated to have the susceptibility of developing with HAM/TSP (Jeffery et al., 1999, 2000). This evidence concerns the gene HLA-A and tropical spastic paraparesis.