Lgi2 is a close homologue of the epilepsy (ADLTE) gene LGI1, and the Lgi2 truncating mutation is closely similar to the most common type of epilepsy-causing mutations in LGI1. The consequence of the truncation on Lgi2 is identical to the consequence of truncation on LGI1, prevention of neuronal secretion and binding to ADAM receptors, which is presently the most favored mechanism of epileptogenesis in ADLTE. The gene discussed is LGI2; the disease is epilepsy.