Although more commonly associated with Rubinstein-Taybi syndrome (RTS), the CREB Binding Protein (CREBBP) gene has been identified as the primary gene of the 16p13.3 microduplication phenotype, along with key genes Glutamate Ionotropic Receptor NMDA Type Subunit 2A (GRIN2A) and RNA Binding Fox-1 Homolog 1 (RBFOX1) [3]. This evidence concerns the gene CREBBP and Rubinstein-Taybi syndrome.