Heme synthase (ferrochelatase) activity, as determined by the chelation of ferrous iron to protoporphyrin or deuteroporphyrin, is reduced to 10-25% of normal in tissues of patients with protoporphyria. With cultured skin fibroblasts from seven patients with protoporphyria and six normal individuals, the present studies examined the enzymatic defect.
Joseph R. Bloomer
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