TFF2, which was also present in all samples, revealed a low protein concentration in healthy samples (13.7 pg/mg, ranging from 2.4 to 74.3 pg/mg) that was hardly changed in cases of OA (9.0 pg/mg, ranging from 0.4 to 45.9 pg/mg), but was strongly increased in cases of RA (203.5 pg/mg, ranging from 0.3 to 835.4 pg/mg) (Figure 3C and Table 3). This evidence concerns the gene TFF2 and rheumatoid arthritis.