Uroporphyrinogen decarboxylase gene mutations in Danish patients with porphyria cutanea tarda

Decreased uroporphyrinogen decarboxylase (UROD) activity is a characteristi c feature of the most-common of the porphyrias, porphyria cutanea tarda (PC T). A subgroup of the clinically overt PCT cases is associated with mutatio ns in the gene encoding UROD and inherited as an autosomal-dominant trait. In this study, DNAs from 53 Danish PCT patients were subjected to genetic a nalysis for UROD mutations using denaturing gradient gel electrophoresis. E leven genetic variations, seven of which are possible disease causing, were identified. All but one of these mutations were previously unknown, lendin g further support to the assumption that PCT is a heteroallelic disease. On ly 11% of the examined patients were previously recognized as familial PCT cases. However, possible disease-related UROD mutations were identified in 24% of the examined patients, indicating that genetic analysis of PCT patie nts may improve differentiation between familial and sporadic PCT cases.