While HBZ was found in the nucleus in leukemic cells, with a speckle-like distribution (Raval et al., 2015; Baratella et al., 2017a,b), in HAM/TSP patients, we found for the first time that HBZ localized in the cytoplasm (Baratella et al., 2017b). The gene discussed is HBZ; the disease is tropical spastic paraparesis.