TUMOR-NECROSIS-FACTOR LOCUS POLYMORPHISMS IN RHEUMATOID-ARTHRITIS

We examined six polymorphic elements in the tumor necrosis factor (TNF ) locus and determined their allelic distribution in 98 Caucasian rheu matoid arthritis patients in comparison with 91 ethnically-matched con trols. Polymorphic elements at four biallelic sites were distributed s imilarly between patients and controls, irrespective of the presence o r absence of DR4. Differences were observed between the two groups at the TNFa and TNFe loci, but these were consistent with extended MHC ha plotypes known to be present in rheumatoid arthritis patients. Therefo re, this study suggests that there is little, if any, independent cont ribution of the TNF locus to the genetic background for rheumatoid art hritis susceptibility.