TNFRSF1A and rheumatoid arthritis: Similarly, in 280 RA patients treated with TNF-inhibitors, an association study of five SNPs in TNF-α and TNF-receptor encoding genes (TNF-α: −308G > A, −238G > A, −857C > T; TNFR1 36A > G; TNFR2 676T > G) was investigated.