So far, only four patients from three unrelated families harbouring recessive GTF3C3 variants have been sporadically described.8-10 Many clinical characteristics are shared between those patients and the four new patients described in this report such as facial dysmorphism, developmental delay, intellectual disability, brain atrophy with predominant cerebellar involvement, hypoplasia of the frontal lobes and diffuse simplification of the gyral pattern of the brain. This evidence concerns the gene GTF3C3 and Intellectual disability.