By James Adams
British researchers have identified a single nucleotide polymorphism in the tumor necrosis factor receptor II gene that is associated with rheumatoid arthritis in Caucasian British patients with a family history of the disease.
Tumor necrosis factor (TNF) plays an important role in development of inflammation in rheumatoid arthritis patients (RA). Its acute effects are limited in vivo by binding to the soluble tumor necrosis factor receptors (TNFRs).
Researchers from the University of Manchester in Manchester, UK, investigated the possible association of polymorphisms of TNFRI and TNFRII with RA.
Genotypes of 291 Caucasian patients with RA and 143 healthy controls were determined for the A/G polymorphism in exon 1 of the TNFRI a gene. Also, 240 patients and 137 controls from the same sample were typed for an single nucleotide polymorphism in exon 6 of the TNFRII gene.
Results showed that the TNFRI polymorphism was not associated with RA.
However, patients with RA were significantly more likely to have the G allele and the GG genotype for TNFRII (odds ratio for GG genotype 2.55, 95 per cent confidence interval 1.11 to 5.86) compared with controls. This association appeared to be confined to patients with a family history of RA.
In a follow-up study
of 149 patients with a family history of RA and 208 patients with sporadic
RA, the family history based relationship was confirmed.
Arthritis Rheum 2001;
44: 41-65. "Association
between rheumatoid arthritis and polymorphism of tumor necrosis factor
receptor II, but not tumor necrosis factor receptor I, in Caucasians"