Born in Alkmaar to Catharina Jacoba Luchtmans, her mother, and Adrianus Petrus de Lange, a prominent lawyer in the city, de Lange was pushed to pursue an education in chemistry by her father.[1][2] She enrolled in the University of Zurich to study chemistry but changed her focus to medicine in 1892.[1] She graduated from the University of Amsterdam in 1897, becoming the fifth woman physician to qualify in the Netherlands.[3][4] However, because pediatrics did not exist as a specialty in the Netherlands, De Lange moved to Switzerland, where she worked in the children's hospital in Zurich under Oskar Wyss.[3] She then returned to Amsterdam and practiced at Emma Kinderziekenhuis (Emma Children's Hospital).[3][4] De Lange worked in all aspects of pediatrics. During her 50 years of practice she collected multiple observations of pediatric disorders.[5] De Lange also became interested in congenital disorders and their pediatric relevance as theories on human genetics developed during the 1920s and 1930s.[5] In 1933, De Lange described what she called "typus degenerativus Amstelodamensis" (Amsterdam degeneration type) in two children, which became known as Cornelia de Lange syndrome.[3] She was knighted in 1947 by the Dutch government as a member of the Order of Orange-Nassau.[6] She died in Amsterdam at the age of 78.[4]
