_:vb50941489 "url:https://ghr.nlm.nih.gov/condition/mecp2-duplication-syndrome"^^ . _:vb50941489 "url:https://rarediseases.info.nih.gov/diseases/9781/mecp2-duplication-syndrome"^^ . _:vb50941489 . _:vb50941489 . _:vb50941489 . _:vb50941489 . _:vb50941489 "A syndrome that has_material_basis_in an extra copy of the MECP2 gene in each cell, occurs almost exclusively in males and that is characterized by delayed development of motor skills such as sitting and walking."^^ .