A Study on TNF-α Gene Polymorphism in RA Patients and its Singificance

Objective To investigate the relationship between tumor necrosis factor-α(TNF-α) gene polymorphism and rheumatoid arthritis (RA). Methods Genomic DNA from 34 RA patients and 35 ethnically matched controls were typed for TNF-α(308) gene polymorphism by allele-specific polymerase chain reaction(AS-PCR). The concentration of their serum TNF-α was measured by ELISA. Results The TNF genotypes in RA patients were respectively TNF 1 homozygote 14 7%, TNF 2 homozygote 52 9%, and TNF 1 and TNF 2 heterozygote 32 4%. TNF genotypes in controls were respectively TNF 1 homozygote 68 6%, TNF 2 homozygote 2 8%, and TNF 1 and TNF 2 heterozygote 28 6%. The significant difference was found in the distribution of TNF-α(308) genotype between the two groups (χ 2=27 71,P0 01). The concentration of the serum TNF-α in RA patients was higher than that in controls(P0 01). And the serum TNF-α concentrations of TNF 2/2 and TNF 2/1 genotypes were higher than those of TNF 1/1 genotype in RA patients (P0 01). Conclusion TNF production in RA patients was influenced by TNF gene polymorphism, which suggested that TNF-α gene polymorphism may play a role in the pathogenesis of RA.