PCBD1

Chr 10AR

pterin-4 alpha-carbinolamine dehydratase 1

Also known as: DCOH, PCBD, PCD, PHS

NCBI Gene: 5092 ENSG00000166228 UniProt: P61457 OMIM: 126090

The encoded protein functions as a dehydratase in tetrahydrobiopterin biosynthesis and as a cofactor for HNF1A-dependent transcription. Mutations cause BH4-deficient hyperphenylalaninemia type D through autosomal recessive inheritance. Enzyme deficiency disrupts tetrahydrobiopterin metabolism, leading to elevated phenylalanine levels.

OMIM ResearchSummary from RefSeq, OMIM, UniProt, Mechanism

This gene encodes a member of the pterin-4-alpha-carbinolamine dehydratase family. The encoded protein has been identified as a moonlighting protein based on its ability to perform mechanistically distinct functions. The encoded protein functions as both a dehydratase involved in tetrahydrobiopterin biosynthesis, and as a cofactor for HNF1A-dependent transcription. A deficiency of this enzyme leads to hyperphenylalaninemia. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2014]

OMIM ResearchGenerating clinical summary…

Primary Disease Associations & Inheritance

Hyperphenylalaninemia, BH4-deficient, DMIM #264070

Clinical highlights

Gene-disease validity (ClinGen)

pterin-4 alpha-carbinolamine dehydratase 1 deficiency · ARDefinitivesufficient evidence for diagnostic panels

Interpreting a novel variant

Loss of function is the curated mechanism (Gene2Phenotype), though the gene is not strongly LoF-constrained in the population — weigh truncating variants against that tolerance.Curated gene-level mechanism — a prior for triage, not a per-variant call.

Active trials

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Pubs (1 yr)

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P/LP submissions

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P/LP missense

1.83

LOEUF

LOF

Mechanism· G2P