This analysis showed that binding HBZ was a significant predictor of proviral load in both ACs and HAM/TSP patients (P = 0.001, P = 0.017), but confirmed the finding that in a traditional analysis HLA-A*02 (presence/absence) was a significant predictor in ACs only (P = 0.01) and HLA-B*54 for HAM/TSP patients only (P = 0.019). This evidence concerns the gene HLA-B and tropical spastic paraparesis.