BHLHA9

Chr 17

basic helix-loop-helix family member a9

Also known as: BHLHF42, CCSPD

NCBI Gene: 727857 ENSG00000205899 UniProt: Q7RTU4

This transcription factor regulates gene expression during limb development and morphogenesis. Mutations cause autosomal recessive syndactyly with mesoaxial synostotic features and phalangeal reduction, as well as complex camptosynpolydactyly. The gene shows tolerance to loss-of-function variants (LOEUF 1.9), consistent with recessive inheritance where both copies must be affected to cause disease.

ResearchSummary from RefSeq, OMIM, UniProt

This gene is a member of the basic helix-loop-helix family. The encoded protein is a transcription factor involved in limb development. Mutations in this gene have been associated with mesoaxial synostotic syndactyly Malik-Percin type (MSSD). Copy number variation of a locus containing this gene has been linked to a form of split-hand/foot malformation with long bone deficiency (SHFLD3). [provided by RefSeq, Mar 2015]

ResearchGenerating clinical summary…

Primary Disease Associations & Inheritance

UniProtSplit-hand/foot malformation with long bone deficiency 3

UniProtSyndactyly, mesoaxial synostotic, with phalangeal reduction

UniProtCamptosynpolydactyly, complex

Clinical highlights

Interpreting a novel variant

A dominant-negative effect is the curated mechanism (Gene2Phenotype), so a variant that simply removes the protein may not be the pathogenic class here — missense variants in functional domains often carry more weight.Curated gene-level mechanism — a prior for triage, not a per-variant call.

Active trials

Pubs (1 yr)

—

P/LP submissions

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P/LP missense

1.89

LOEUF

Mechanism· G2P

Some data sources returned errors (1)

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