Background: Anti-NOR 90 autoantibodies (anti-NOR90 Ab) are that target nucleolar transcription factor 1 or hUBF, involved in of RNA polymerase I. These have been detected 6.1% patients with Systemic Sclerosis (SSc), but their clinical prognostic significance has not clearly defined. Anti-NOR90 Ab mostly associated limited scleroderma mild organ involvement and can also be found other rheumatic ...