TNF+489 polymorphism does not contribute to susceptibility to rheumatoid arthritis

Objectives. To determine if a tumour necrosis factor (TNF +489) polymorphism is associated with susceptibility to rheumatoid arthritis (RA). Methods. Two European populations were studied: 217 controls and 238 patients from the north of England and 145 controls and 179 patients from Spain. HLA-DRBI and TNF+489 markers were typed using polymerase chain reaction based methods. Results. Strong associations were demonstrated with shared epitope (SE) encoding HLA-DRB1 alleles in the English (OR= 2. 9 [2.2-3.9]) and Spanish (OR= 2.3 [1.6-3.3]) populations, however no association was found with TNF+489 alleles. Furthermore carriage of TNF+489A was not associated with the presence of radiological erosions, rheumatoid nodules or rheumatoid factor. Conclusion. The role of the TNF locus in the genetic background of RA is unclear, however, our data does not support the previous reported association of the TNF+489A allele with RA susceptibility or severity.