

Porphyrias are a rare group of disorders passed down through families in which an important part of hemoglobin, called heme, does not develop properly. Heme is also found in myoglobin, a protein found in certain muscles.
Acute intermittent porphyria; Hereditary coproporphyria; Congenital erythropoietic porphyria; Erythropoietic protoporphyria