IL17A Polymorphism Is Not Associated with Human T-Lymphotropic Virus 1-Associated Myelopathy/Tropical Spastic Paraparesis

The human T-lymphotropic virus 1 (HTLV-1) is the causative agent of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The present study investigated the association between the rs2275913 polymorphism in the IL17A gene and the development of HAM/TSP. Peripheral blood samples were collected from 116 patients (29 symptomatic patients with HAM/TSP and 87 asymptomatic) with a positive diagnosis of HTLV-1. The single nucleotide polymorphism genotyping was carried out by real time quantitative PCR (RT-qPCR) using TaqMan (R) probes. In addition, serum levels of IL-2, IFN-gamma, TNF-alpha, IL-4, IL-6, IL-10, and IL-17 were measured in 64 infected individuals from the study (47 asymptomatic and 17 HAM/TSP), using cytometric bead array technique. No significant differences were found in genotypic and allelic frequencies between the groups. Analysis of cytokine levels showed highest concentrations of IFN-gamma and TNF-alpha in HAM/TSP patients. The results of the present study, therefore, suggest a lack of association between the rs2275913 polymorphism in the IL17A gene and the presence of HAM/TSP.