2009). Children with less severe ID may be under represented in research cohorts used for exome sequencing analysis; in this case, the presentation of epilepsy in the neonatal period, which resolved only to remerge later in childhood, was one of the reasons for exome sequencing having been performed. It is possible, therefore, that there are other mutations in EEF1A2 underlying many more cases of mild ID. Here, EEF1A2 is linked to epilepsy.