EP300 and Wiedemann-Steiner syndrome: Notably, EP300-associated RSTS2 demonstrates substantial phenotypic overlap with multiple Mendelian disorders, including Floating-Harbor syndrome (FHS; OMIM #136140), Cornelia de Lange syndrome (CDLS; OMIM #122470), and Wiedemann-Steiner syndrome (WDSTS; OMIM #605130) and others.