Brain somatic mutations in genes belonging to the mTOR pathway are well recognized in
malformations of the cortical development, such as focal cortical dysplasia or
hemimegalencephaly. The present study aims to search for brain somatic mutations in paired
blood-brain samples from children undergoing epilepsy surgery at the Rothschild Foundation,
Paris. Patients and their parents will be recruited to identify genetic abnormalities both in
lymphocytic and cortical DNA.