Total nuclear HAT activity was measured in synovial tissues from normal controls (7.04 ± 1.78 μM, n = 3), from OA (7.23 ± 1.35 μM, n = 5) and from RA (6.28 ± 1.06 μM, n = 5) (Figure 1b). This evidence concerns the gene TMPRSS11D and rheumatoid arthritis.