AbstractBackground. Recent data have supported an autoimmune etiology of vitiligo. Genetic factors also seem to play an important role in this disorder. The purpose of this study was to determine the presence and frequency of organ‐specific autoantibodies in vitiligo patients and their relatives.Methods. Twenty patients with vitiligo and two first or second degree relatives of each patient were interviewed and their sera analyzed for the presence of antithyroglobulin (ATg), antithyroid microsomal (ATM), antiparietal cell (APC), and antiadrenal (AAd) autoantibodies. The sera of 20 normal patients were used as control.Results. A significantly increased frequency of ATg, ATM, and APC antibodies was found in vitiligo patients when compared to normal controls. First and second degree relatives had significantly increased frequencies of ATg and ATM. A high incidence of autoimmune/endocrine diseases was found in the patients' relatives, including a 25% prevalence of vitiligo.Conclusions. These findings not only support an autoimmune etiology for vitiligo, but also highlight the strong genetic contribution to this pigmentary disorde