In the present dataset, the above-mentioned NFIL3, JUND, MAT2A, and TIPARP were indeed significantly overexpressed in the synovial membrane of CG as compared with both RA and OA (both individually for the three different clinical centers and for the pooled study group ‘Total’ derived from all centers; Additional file 5). This evidence concerns the gene MAT2A and rheumatoid arthritis.