Abstract: Objective To investigate family history, sex, age of onset, disease severity and environmental predisposing factors in vitiligo patients. Methods Eight hundred and fifteen vitiligo patients were investigated by questionnaires. Patients with family history were compared with those without such history. SPSS 10.0 software package was applied for data analysis. Results Of 815 vitiligo probands, 128 had family history and 687 did not. The heritability rate was 15.7%. Compared with general population, vitiligo probands with affected fathers or mothers had a relative risk (RR) of 132 or 72, respectively. The RRs of those with affected first-degree relatives varied from 12 to 28. There was no significant difference of mean age of onset and disease severity between patients of paternal inheritance and maternal inheritance. No significant difference was found regarding sex and mean age of onset between the groups with and without family history. However, the patients with family history were more likely to have scattered, bilateral distributed and progressive vitiligo. Of the environmental predisposing factors, the mean daily sun-exposure time was closely related to vitiligo in patients with family history. Conclusion Genetic factors may play an important role in the pathogenesis and disease severity of vitiligo.

Key words: Vitiligo, Genetic predisposition to disease