RNPC3 and systemic sclerosis: In patients with no specific autoantibodies (beyond ANA), the median (IQR) ISG score was 0.407 (0.303, 0.998) and there was a significant increase in ISG score as the total number of autoantibodies in each patient (defined as anti-dsDNA, anti-Smith, anti-RNP, anti-Ro, anti-La, anti-CCP, anti-chromatin/nucleosome or SSc-specific antibodies [anti-centromere, anti-Scl-70 or RNA polymerase III]) increased (Kruskal-Wallis, p = 0.0001) (Fig. 2b).