ELP2 is a novel gene implicated in neurodevelopmental disabilities.

Elongator is a multi-subunit protein complex essential to transcription elongation, histone acetylation, and tRNA modification. The complex consists of six highly conserved protein subunits, called Elongator Proteins (ELP) 1-6. Apart from an association with intellectual disability (ID), there is limited clinical information about patients with ELP2 variants. Here we report on two brothers with severe ID, spastic diplegia, and self-injury whose presentation eluded a diagnosis for over 20 years. In both brothers, whole exome sequencing revealed a likely pathogenic, compound heterozygous missense variant in ELP2. We describe the phenotype and natural history of the ELP2-related disorder in these brothers.