Polymorphism of the 5′-Flanking Region of the Tumor Necrosis Factor (TNF)-α Gene and Susceptibility to Human T-Cell Lymphotropic Virus Type I (HTLV-I) Uveitis

0-flanking promoter/ enhancer region of the tumor necrosis factor (TNF)‐a gene in patients with HU, together with patients with adult T-cell leukemia (ATL), asymptomatic HTLV-I carriers, and healthy controls. The frequencies of the 21,031C allele (TrC transition at position 21,031) and 2863A allele (CrA transition at position 2863) in the HU patients, but neither in the ATL patients nor in the carriers, were significantly higher than those in the controls. The 21,031C and 2863A alleles, in the absence of the HLA B61 or the DRB1*0901 allele which is in linkage disequilibrium with these alleles, were associated with increased susceptibility to HU. These results suggest that the 21,031C and 2863A alleles might be genetic risk factors for HU. Human T-cell lymphotropic virus type I (HTLV-I), causative for adult T-cell leukemia/lymphoma (ATL), is involved in tropical spastic paraparesis/HTLV-I‐associated myelopathy (TSP/ HAM) and HTLV-I uveitis (HU), although the vast majority of HTLV-I‐infected subjects are asymptomatic [1, 2]. The molecular mechanisms by which HTLV-I causes these different diseases in a minority of HTLV-1‐infected subjects have not been fully addressed. Previous studies have demonstrated that HLA haplotypes associated with ATL are different from those