Molecular characterization of HTLV-1 genomic region hbz from patients with different clinical conditions.

The human T-cell lymphotropic virus type-1 (HTLV-1) is associated with severe pathologies, such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), adult T-cell leukemia-lymphoma (ATLL), and infective dermatitis associated with the HTLV-1 (IDH). Interestingly, HTLV-1 infection does not necessarily imply the development of pathological processes and it is unknown why some patients remain asymptomatic carriers (AC). Despite some mutations in the HTLV-1 genome appear to influence the outcome of HTLV-1, there are few studies that characterize molecularly the hbz region. This study aimed to perform the molecular characterization of hbz gene isolated from patients with different clinical outcomes. A total of 15 sequences were generated and analyzed with 571 sequences previously published. The analises showed that the R119Q mutation seems to be related to HTLV-1 clinical conditions since the frequency of this HBZ mutation is significantly different in comparison between AC with HAM/TSP and ATLL. The R119Q mutation is possibly a protective factor as the frequency is higher in AC sequences.