Acetylation deficits, tipping the balance between KATs and HDACs in favor of HDACs, are a recognized cause of impaired cognition in neurodevelopmental disorders of the epigenetic machinery, like Rubinstein-Taybi [9], as well as in neurodegenerative disorders where CBP-dependent transcription is altered [21]. The gene discussed is CREBBP; the disease is neurodevelopmental disorder.