Catalyzes the decarboxylation of four acetate groups of uroporphyrinogen-III to yield coproporphyrinogen-III.
Porphyrin metabolism; protoporphyrin-IX biosynthesis; coproporphyrinogen-III from 5-aminolevulinate: step 4/4.
Defects in UROD are the cause of familial porphyria cutanea tarda (FPCT) [MIM:176100]; also known as porphyria cutanea tarda type II. FPCT is an autosomal dominant disorder characterized by light-sensitive dermatitis, with onset in later life. It is associated with the excretion of large amounts of uroporphyrin in the urine. Iron overload is often present in association with varying degrees of liver damage. Besides the familial form of PCT, a relatively common idiosyncratic form is known in which only the liver enzyme is reduced. This form is referred to as porphyria cutanea tarda "sporadic" type or type I [MIM:176090]. PCT type I occurs sporadically as an unusual accompaniment of common hepatic disorders such as alcohol-associated liver disease. Defects in UROD are the cause of hepatoerythropoietic porphyria (HEP) [MIM:176100]. HEP is a rare autosomal recessive disorder. It is the severe form of cutaneous porphyria, and presents in infancy. The level of UROD is very low in erythrocytes and cultured skin fibroblasts, suggesting that HEP is the homozygous state for porphyria cutanea tarda.
Belongs to the uroporphyrinogen decarboxylase family.