Provided are methods for prophylaxis and/or therapy for Phelan-McDermid Syndrome (PMS) and autism spectrum disorder (ASD). The methods involve administering a histone methyltransferase (HMT) inhibitor, a histone deacetylase (HDAC) inhibitor, or a combination thereof, such that one or more symptoms of the PMS and/or the AMD are reduced.
Use of histone methyltransferase inhibitors and histone deacetylase inhibitors for therapy of Phelan-McDermid Syndrome