Regarding the onset age, undiagnosed isolated Ro52 positive patients are older (mean onset age 53,6) if we compare them with the group of isolated Ro52+ with SLE (mean onset age of 49,2) and younger than isolated Ro52+SS patients in this series of patients (mean onset age of 61,8) (data not shown). Here, TRIM21 is linked to systemic lupus erythematosus.