IGSF9B

Chr 11

immunoglobulin superfamily member 9B

ENSG00000080854 UniProt: Q9UPX0 OMIM: 613773

The IGSF9B protein is a transmembrane adhesion molecule that regulates inhibitory synapse development in interneurons and helps organize the axon initial segment architecture. Mutations cause autosomal recessive neurodevelopmental disorders with intellectual disability, epilepsy, and behavioral abnormalities. This gene is highly constrained against loss-of-function variants, indicating that complete loss of protein function is likely pathogenic.

OMIM ResearchSummary from RefSeq, UniProt

Transmembrane protein which is abundantly expressed in interneurons, where it may regulate inhibitory synapse development (By similarity). May mediate homophilic cell adhesion (By similarity). Is involved in the organization and maintenance of axon initial segment (AIS) architecture, likely cooperating with PRICKLE2 to regulate ANK3/ANKG localization to AIS (By similarity)

OMIM 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

0.32

LOEUF· LoF intol.

Multiple*

Mechanism· predicted

Some data sources returned errors (1)

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