Dr. Casanova received his M.D. from the University of Paris Descartes in 1987 and his Ph.D. in immunology from the University of Paris Pierre and Marie Curie in 1992. After completing a residency in pediatrics and a clinical fellowship in pediatric immunology-hematology, he was appointed a professor of pediatrics at the Necker Medical School in Paris. There, with Dr. Abel, he cofounded and codirected the Laboratory of Human Genetics of Infectious Diseases in 1999. He was appointed professor at Rockefeller in 2008 and named a Howard Hughes Medical Institute investigator in 2014.