CYRIB

Chr 8

CYFIP related Rac1 interactor B

Also known as: BM-009, CYRI, CYRI-B, FAM49B, L1

NCBI Gene: 51571 ENSG00000153310 UniProt: Q9NUQ9

The CYRIB protein negatively regulates RAC1 signaling and controls cytoskeletal remodeling, cell migration, and mitochondrial dynamics while also protecting against bacterial infections. Mutations cause autosomal dominant developmental and epileptic encephalopathy with microcephaly, affecting the brain and resulting in seizures and developmental delays typically beginning in infancy. The gene is highly constrained against loss-of-function variants, indicating that such mutations are likely to be pathogenic.

ResearchSummary from RefSeq, UniProt

Enables small GTPase binding activity. Involved in several processes, including negative regulation of actin filament polymerization; negative regulation of small GTPase mediated signal transduction; and regulation of mitochondrial fission. Located in mitochondrion. [provided by Alliance of Genome Resources, Jun 2026]

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)

—

P/LP submissions

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P/LP missense

0.31

LOEUF· LoF intol.

Multiple*

Mechanism· predicted

Some data sources returned errors (1)

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