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. Highlights Generation and analysis of 15 new HTLV‐1 hbz sequences and 571 hbz sequences from GenBank. Mutation R119Q is more frequent in HBZ sequences from asymptomatic individuals than in HAM/TSP and ATLL individuals. Mutation R119Q is more frequent in HBZ sequences from asymptomatic individuals than in HAM/TSP and ATLL individuals.