Gene expression at mRNA level was detected for Treg-related genes–FOXP3, TGFB1, and IL10 and genes encoding pro-inflammatory cytokines–IL23A, IL12B, TNFA, IL17A, and IL18 in the cohort of 31 patients diagnosed with RA, compared to 21 age-matched healthy controls. Here, IL12B is linked to rheumatoid arthritis.