While circulating IgA cells were lower in both mass cytometry and BCR sequence analysis, when we analyzed total IgA levels in 2194 RA patients 1300 population controls (Fig. 4, Supplemental Table 10), we found that IgA levels were significantly elevated in RA compared to controls (2.32 ± 1.0 [median 2.21] vs 1.58 ± 0.80 mg/ml [median 1.51], p < 0.0001). This evidence concerns the gene BCR and rheumatoid arthritis.