Genetic ancestry of patients with porphyria cutanea tarda in a country with mixed races: a cross-sectional study (Rio de Janeiro - Brazil).

Porphyria cutanea tarda has a complex etiology with genetic factors not completely elucidated. The miscegenation of the Brazilian population has important implications in the predisposition to diseases. There are no studies concerning the genetic ancestry of patients with porphyria cutanea tarda from a mixed population.