The first phase of this study uncovered evidence that ZDHHC9 mutations are associated with susceptibility to focal seizures sharing features with rolandic epilepsy (RE; also known as Benign Childhood Epilepsy with CentroTemporal Spikes, BECTS), the most frequently diagnosed epilepsy syndrome of childhood.6,7 Having identified this unexpected association, we posed two targeted hypotheses. This evidence concerns the gene ZDHHC9 and epilepsy syndrome.