Polymorphism at the TNF loci in rheumatoid arthritis.

The purpose of this work was to analyze the possible influence of TNF loci polymorphism on the susceptibility and/or the disease profile of rheumatoid arthritis (RA). Tumor necrosis factor (alpha and beta) genotypes were determined in 60 patients with RA and 102 healthy subjects by a method based on PCR-RFLP with amplification-created restriction sites. The results obtained in the present study showed that there is not a significant association of either TNF alpha promoter variation (at positions -308 and -238) or TNF beta polymorphism with susceptibility to RA. However, a significant difference in the mean age at disease onset was found between -238 TNF alpha genotypes. In addition, a difference in the presence of nodular disease was observed between -308 TNF alpha genotype. The results of this study suggests that the TNF alpha gene may play a role in the disease profile of rheumatoid arthritis.