GTR Home > Conditions/Phenotypes > hyperphenylalaninemia, bh4-deficient, d


Tetrahydrobiopterin (BH4)-deficient hyperphenylalaninemia (HPA) D is an autosomal recessive disorder characterized by mild transient hyperphenylalaninemia often detected by newborn screening. Patients also show increased excretion of 7-biopterin. Affected individuals are asymptomatic and show normal psychomotor development, although transient neurologic deficits in infancy have been reported (Thony et al., 1998). Patients may also develop hypomagnesemia and nonautoimmune diabetes mellitus during puberty (summary by Ferre et al., 2014). For a general phenotypic description and a discussion of genetic heterogeneity of BH4-deficient hyperphenylalaninemia, see HPABH4A (261640). [from OMIM]

Available tests

41 tests are in the database for this condition.

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Genes See tests for all associated and related genes

  • Also known as: DCOH, PCBD, PCD, PHS, PCBD1
    Summary: pterin-4 alpha-carbinolamine dehydratase 1

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