DENND4C

Chr 9

DENN domain containing 4C

Also known as: C9orf55, C9orf55B, RAB10GEF, bA513M16.3

NCBI Gene: 55667 ENSG00000137145 UniProt: Q5VZ89

The protein functions as a guanine nucleotide exchange factor that activates RAB10 and promotes insulin-stimulated glucose transporter delivery to the plasma membrane. Mutations cause autosomal recessive developmental and epileptic encephalopathy with microcephaly, which presents in early infancy with severe epilepsy, developmental delay, and progressive microcephaly. The gene shows high intolerance to loss-of-function variation, indicating that complete protein loss is likely incompatible with normal development.

ResearchSummary from RefSeq, UniProt

Enables guanyl-nucleotide exchange factor activity. Predicted to be involved in cellular response to insulin stimulus; protein localization to plasma membrane; and regulation of Rab protein signal transduction. Located in Golgi apparatus and cytosol. [provided by Alliance of Genome Resources, Jul 2025]

ResearchGenerating clinical summary…

Clinical highlights

Interpreting a novel variant

This gene is strongly intolerant of loss-of-function variation in the population, so LoF variants warrant close attention. No curated mechanism annotation is available — see the mechanism card for the computational prediction and its caveats.Based on population constraint only.

Active trials

Pubs (1 yr)

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P/LP submissions

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P/LP missense

0.45

LOEUF

Mechanism· predicted