The results found corroborate other studies that report that the increase in the frequency of cells expressing TNF-α is directly associated with the pathogenesis of HTLV-1 infection, contributing to the exacerbated inflammatory environment observed in conditions such as HAM (Santos et al., 2004; Nakamura et al., 1993; Neco et al., 2017). The gene discussed is TNF; the disease is tropical spastic paraparesis.