Characteristics of genetic epidemiology and genetic models for vitiligo.

Background: Vitiligo occurs with a frequency of 0.1% to 2% in various populations and is classified into several subtypes by its clinical presentation. Although genetic factors are thought to be involved in the cause of vitiligo, the genetic models for different phenotypes of vitiligo are unknown.

Objective: Our purpose was to explore potential genetic models for different phenotypes of vitiligo and analyze genetic epidemiologic characteristics of vitiligo in a Chinese population.

Methods: Information from 2247 patients and members in their families was collected using a uniform questionnaire. Patients' clinical characteristics and their family history were analyzed using software. A complex segregation analysis was conducted to propose potential genetic models for vitiligo.

Results: Different subtypes of vitiligo had different ages of disease onset. In relatives of patients with vitiligo, the risk of developing vitiligo increased with increasing relatedness to the patients with vitiligo. A polygenic additive model was the best model for focal vitiligo, vitiligo vulgaris, acrofacial vitiligo, and segmental vitiligo with approximately 50% heritability in each. For universal vitiligo, the best model was an environmental model.

Conclusion: This study indicated that different phenotypes of vitiligo had different pathogeneses and genetic backgrounds. Onset of vitiligo is possibly affected by both genetic backgrounds and common environmental factors.