TNF and rheumatoid arthritis: Examination of SNPs in TNF-α gene, and its receptors (TNFRSF1A/TNFRSF1B), in RA patients compared to HCs, reported that some SNPs, TNFRSF1A:rs767455 and TNFRSF1B:rs3397, are linked to TNFRSF1B downregulation, increased susceptibility to MAP infection, increased inflammation and osteocalcin deficiency, and, possibly, increased osteoporosis [120].