Lack of evidence to support the association of a single IL28B genotype SNP rs12979860 with the HTLV-1 clinical outcomes and proviral load

Abstract\ud \ud Background\ud The Interleukin 28B (IL28B) rs12979860 polymorphisms was recently reported to be associated with the human T-cell leukemia virus type 1 (HTLV-1) proviral load (PvL) and the development of the HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP).\ud \ud \ud Methods\ud In an attempt to examine this hypothesis, we assessed the association of the rs12979860 genotypes with HTLV-1 PvL levels and clinical status in 112 unrelated Brazilian subjects (81 HTLV-1 asymptomatic carriers, 24 individuals with HAM/TSP and 7 with Adult T cell Leukemia/Lymphoma (ATLL)).\ud \ud \ud Results\ud All 112 samples were successfully genotyped and their PvLs compared. Neither the homozygote TT nor the heterozygote CT mutations nor the combination genotypes (TT/CT) were associated with a greater PvL. We also observed no significant difference in allele distribution between asymptomatic carriers and patients with HTLV-1 associated HAM/TSP.\ud \ud \ud Conclusions\ud Our study failed to support the previously reported positive association between the IL28B rs12979860 polymorphisms and an increased risk of developing HAM/TSP in the Brazilian population