Tumor necrosis factor microsatellite alleles in patients with rheumatoid arthritis in Taiwan

The association of DRB1*04 share epitope alleles and tumor necrosis factor-alpha gene polymorphism (−863) with susceptibility to rheumatoid arthritis in Thai

Rheumatoid arthritis (RA) in Thai population is significantly associated with HLA-DR4 shared epitope (SE) alleles, particularly with DRB1*0405 (P = 0.00004, OR = 3.84, 95% CI = 1.93, 7.7). In addition, tumor necrosis factor-alpha (TNF-alpha) gene -863A alleles were found to be significantly increased in 77 RA patients compared to 162 healthy controls (P = 0.03, OR = 1.73, 95% CI = 1.05, 2.87). Interestingly, TNF-863 AC and SE have a synergistic effect on the susceptibility to RA. The OR for the presence of both risk factors (DR4 SE and -863 AC) was cumulative: 15.4 (95% CI = 3.75, 73.6) while the separate OR of DR4 SE and -863 AC were 3.84 and 2.36, respectively. The TNF was not associated with the clinical manifestation and severity of Thai RA patients. However, a highly significant association was found between RF positivity, one marker for severity, and RA patients with DR4 SE (P = 0.0005, OR = 9.42, 95% CI = 2.26, 45.27).

Associations of HLA microsatellites with rheumatoid arthritis in Singaporean Chinese

Rheumatoid arthritis in Singaporean Chinese has previously been shown to be associated with the DRB1*0405, DRB1*1001 haplotypes and to the DRB1*0901 haplotype when the former two were removed. The present paper focused on eight HLA associated microsatellite markers (TNFa, TNFd, D6S273, TAP1CA, DQCAR, DQCARII, D6S2222, D6S2223) and their allelic associations with Chinese RA. 60 RA patients and 75 healthy controls were studied. It appeared that DQCARII*194/DRB1*0405/TNFa*117 was part of the extended haplotype predisposed to RA, whereas DRB1*0901/D6S273*128 contributed to susceptibility to RA to a lesser degree in Singaporean Chinese. Additionally, a negative association with DQCAR*186/DRB1*0301/D6S273*122/TNFd*124 was observed. No association with disease development was observed in this study.