USP9X and Pfeiffer syndrome: Syndromic diagnoses in our cohort included short-rib thoracic dysplasia syndrome, Larsen syndrome (OMIM #150250), Sotos syndrome (OMIM #117550), Pfeiffer syndrome (OMIM #101600), congenital contractural arachnodactyly (OMIM #121050), Intellectual Developmental Disorder X-Linked Type 99 (USP9X-related disease, OMIM #300919), X-linked syndromic mental retardation Turner Type (HUWE1-related disease, OMIM #309590), Freeman-Sheldon syndrome (OMIM #193700), spondylocostal dysostosis (OMIM #608681), and Shwachman-Diamond syndrome (OMIM #260400).