U1 and systemic sclerosis: Other autoantibodies associated with cardiac manifestations in SSc include the following: anti-RNAP III anti-U3 RNP or anti-fibrillarin, anti-Ku antibodies, anti-histone antibodies, anti-Th/To antibodies, AHA, AIDA, anti-U1 ribonucleoprotein antibodies (anti-U1 RNP), anti-Pm/Scl antibodies (anti-PmScl), anti-Ro/Sjögren’s-syndrome-related antigen A antibodies (anti-Ro/SSA), anti-PL-7 and anti-PL-12 antibodies (anti-PL-7/anti-PL-12), anti–nucleolar organizing region 90 antibodies (anti-NOR90), and anti-Mi-2 antibodies [41].