HES5 and Intellectual disability: Amongst the top 30 down-regulated HDACi consensus transcripts, we identified crucial markers for neurodevelopment such as LHX2, HES5, SIX3 (homeobox protein SIX3; crucial for forebrain development; mutations: holoprosencephaly) and ARX (aristaless-related homeobox; mutations are associated with neurological and neurodevelopmental disorders such as lissencephaly, epilepsy, mental retardation) (Fig. 3c).