Early infantile epileptic encephalopathies (EIEEs) constitute a group of severe early onset epilepsies. Although still classified under syndromic clusters of clinical features, the genetic basis of several EIEEs leads to the definition of new types of epilepsies. We report a newborn male with seizures since his second day of life. The results of the first line diagnostic tests did not identify the cause of the seizures, which prompted a genetic study. A de novo KCNQ2 genomic variant that may explain the neonatal epileptic encephalopathy was found and led to more appropriate treatment. Genetic testing allows more specific treatment and more accurate prognosis, and also adds to the database of the phenotypes associated with the genomic variants.