[8] She then became a hematology fellow at Yale University under the supervision of Edward J Benz Jr, during which she worked on the molecular genetics of globin genes and oncogenes.
[12] High moved to the University of Pennsylvania and Children's Hospital of Philadelphia, where she began pioneering gene therapies for blood disorders.
[14] She was the director of the Center for Cellular and Molecular Therapeutics, and as of 2001[update] head of hematology research,[1] at the Children's Hospital of Philadelphia and an investigator of the Howard Hughes Medical Institute.
From 2014 to 2020, High served as the co-founder, President, Chief Scientific Officer/Head of R&D and a Member of the Board of Directors of Spark Therapeutics, a fully integrated, commercial gene therapy company in Philadelphia.
While at Spark Therapeutics, Dr. High led the team that obtained the first FDA approval of an AAV therapeutic (Voretigene neparvovec for the treatment of an inherited disorder causing blindness) in December 2017 and led the team that obtained Breakthrough Therapy designation and FDA approval for Fidanacogene elaparvovec to treat Hemophilia B and Breakthrough Therapy designation for Dirloctogene samoparvovec to treat Hemophilia A.