CPOX
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Gene summaries condense public reference material; disease links and population data change as databases are updated. Clinical decisions belong with your care team.
coproporphyrinogen oxidase
Normal Function
Health Conditions Related to Genetic Changes
Porphyria
At least 45 mutations in the CPOX gene have been found to cause porphyria. Mutations in this gene can cause two types of porphyria: hereditary coproporphyria and a variant known as harderoporphyria.
Most CPOX gene mutations change single protein building blocks (amino acids) in coproporphyrinogen oxidase. A single mutation appears to be responsible for harderoporphyria; this genetic change replaces the amino acid glycine with the amino acid glutamic acid at position 404 (written as Lys404Glu or K404E). Mutations in the CPOX gene reduce the activity of coproporphyrinogen oxidase, allowing compounds called porphyrins to build up in the body. These compounds are formed during the normal process of heme production, but reduced activity of coproporphyrinogen oxidase allows them to accumulate to toxic levels. This buildup, in combination with nongenetic factors such as certain drugs, alcohol, and dieting, leads to the signs and symptoms of hereditary coproporphyria and harderoporphyria.
More About This Health ConditionRelated Conditions
Porphyria
Health Conditions Related to Genetic Changes
At least 45 mutations in the CPOX gene have been found to cause porphyria. Mutations in this gene can cause two types of porphyria: hereditary coproporphyria and a variant known as harderoporphyria.
Most CPOX gene mutations change single protein building blocks (amino acids) in coproporphyrinogen oxidase. A single mutation appears to be responsible for harderoporphyria; this genetic change replaces the amino acid glycine with the amino acid glutamic acid at position 404 (written as Lys404Glu or K404E). Mutations in the CPOX gene reduce the activity of coproporphyrinogen oxidase, allowing compounds called porphyrins to build up in the body. These compounds are formed during the normal process of heme production, but reduced activity of coproporphyrinogen oxidase allows them to accumulate to toxic levels. This buildup, in combination with nongenetic factors such as certain drugs, alcohol, and dieting, leads to the signs and symptoms of hereditary coproporphyria and harderoporphyria.