PRMT5 and rheumatoid arthritis: Receiver operating characteristic (ROC) curve analysis yielded area under the curve (AUC) values of 0.768 for RA (p < 0.0001) and 0.903 for SSc (p < 0.0001), indicating moderate to high discriminatory ability of anti-PRMT5 antibody levels in differentiating these diseases from controls (Fig. 1B).