Genetically engineered mice lacking expression of either the laforin (Epm2a−/−) or malin (Epm2b−/−) genes display a number of neurological and behavioral abnormalities that resemble those found in patients suffering from Lafora disease; of these, both Epm2a−/− and Epm2b−/− mice have shown altered motor activity, impaired motor coordination, episodic memory deficits, and different degrees of spontaneous epileptic activity. The gene discussed is EPM2A; the disease is Lafora disease.