Serum anti-ENO1 antibody titers showed statistically significant correlations with values of PD indices such as PPD (r = 0.16, p = 0.013 by Spearman test), BOP (r = 0.14, p = 0.023), and CAL (r = 0.15, p = 0.017) in RA (Table 2). This evidence concerns the gene ENO1 and rheumatoid arthritis.