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GTR Home > Conditions/Phenotypes > Hyperphenylalaninemia due to DNAJC12 deficiency

Hyperphenylalaninemia due to DNAJC12 deficiency

Synonyms
Hyperphenylalaninemia, mild, non-bh4-deficient
Modes of inheritance
Autosomal recessive inheritance (Orphanet)

Summary

Mild non-BH4-deficient hyperphenylalaninemia (HPANBH4) is an autosomal recessive disorder characterized by increased serum phenylalanine (HPA) usually detected by newborn screening and associated with highly variable neurologic defects, including movement abnormalities, such as dystonia, and variably impaired intellectual development. Laboratory analysis shows dopamine and serotonin deficiencies in the cerebrospinal fluid, and normal tetrahydrobiopterin (BH4) metabolism. Evidence suggests that treatment with BH4 and neurotransmitter precursors can lead to clinical improvement or even prevent the neurologic defects if started in infancy (summary by Anikster et al., 2017). The phenotype is highly variable: some patients may present with later onset of juvenile or young adult nonprogressive dopa-responsive parkinsonism reminiscent of early-onset Parkinson disease (168600). These patients benefit from treatment with L-dopa (summary by Straniero et al., 2017). In a review of HPA, Blau et al. (2018) noted that molecular screening for DNAJC12 mutations should be mandatory in patients in whom deficiencies of PAH (612349) and BH4 metabolism have been excluded. [from OMIM]

Available tests

19 tests are in the database for this condition.

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Clinical tests (19 available)

Biochemical Genetics Tests

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: HPANBH4, JDP1, DNAJC12
    Summary: DnaJ heat shock protein family (Hsp40) member C12

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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