functional polymorphism of the granulocyte macrophage colony stimulating factor is not associated with the outcome of HTLV-I infection

ABSTRACT

Genetic background has known to be associated with the outcome of human T cell lymphotropic virus [HTLV] type I infection. In The present study we investigate the association between GM-CSF gene polymorphisms with the outcome of HTLV-I infection. We analyzed 3 single-nucleotide polymorphisms in the promter region of granulocyte macrophage colony stimulating factor [GM-CSF] at positions -677A/C, -1440A/G and -1916T/C in 68 patients with HTLV- I-associated myelopathy/tropical spastic paraparesis [HAM/TSP] and 77 HTLV-I-seropositive asymptomatic carriers and 175 healthy controls from an area in Iran, Mashhad, where HTLV-I is endemic. No significant differences were observed in the distribution of GM-CSF polymorphisms between HAM/TSP patients, HTLV-I carriers and healthy controls [P> 0.05]. The -611A/C polymorphism fall within the transcriptional enhancer factor-2 [TEF-2] binding site, so an electrophoretic mobility shift assay [EMSA] was performed to determine the effects of polymorphisms on protein binding to the GM-CSF promoter. The result showed a significantly higher binding efficiency of nuclear protein to the A allele compared with the C allele. Our study suggests that polymorphisms in the GM-CSF promoter is not associated with the outcome of HTLV-I infection, however, GM-CSF polymorphism at position -677 could indeed influence gene expression