Leon Rosenberg, MD, former dean of the Yale School of Medicine and inaugural chair of the Department of Genetics, died July 22, 2022.
A pioneer physician-scientist in the discovery, understanding, and treatment of human metabolic disorders, Rosenberg will be remembered for his pioneering vision in founding the department, for his discoveries in human genetics, and for his exceptional service to Yale as dean. from the School of Medicine from 1984 to 1991. He later became president of Bristol-Myers Squibb’s Pharmaceutical Research Institute and senior molecular biologist and professor at Princeton University.
Rosenberg came to Yale as the inaugural chief of a joint division of Medical Genetics in the Departments of Pediatrics and Internal Medicine. In 1963, two years before arriving to lead research into genetic defects in the metabolism of amino acids and organic acids, he told a prominent Yale nephrologist that he intended to specialize in medical genetics. “Don’t be silly,” the nephrologist replied. “There’s no such thing.” Time, and Rosenberg, would prove that prediction wrong.
Rosenberg received his BA and MD degrees from the University of Wisconsin and completed his internship and first year of internal medicine training at Columbia-Presbyterian Medical Center in New York. His interest in genetics and metabolic diseases began during his six years at the National Cancer Institute (NCI), where he treated an eight-year-old boy who eventually died of a debilitating condition of his skeletal muscles. Two siblings with nearly identical cases had died before him.
He came to Yale in 1965 and in 1972 he was the founder of the Department of Human Genetics, the first of its kind in the US. He also led the first clinical genetics department at Yale New Haven Hospital. Rosenberg became the 13th Dean of the Yale School of Medicine in 1984 and served for seven years. During his tenure, a four-year capital campaign raised $155 million and completed the Magnetic Resonance Center. The Yale Physicians Building, the Boyer Center and the Yale Psychiatric Institute opened their doors and work began on an addition to the medical library.
In an effort to enrich the school’s academic life, he created a task force that recommended putting greater emphasis on teaching and increasing the number of women in senior faculty positions. He was committed to improving the health of people who are medically and socio-economically disadvantaged and encouraged students, teachers and staff to participate in community service. He created the Office of Minority Affairs as part of a plan to address the issues raised by minority students. His goals included increasing the number of minority students and faculty at the School of Medicine; allow medical and public health students to volunteer at New Haven public schools; and adopting a code of conduct “that condemns racism and insensitivity in all forms”.
After stepping down as dean in 1991 to lead Bristol-Myers Squibb’s pharmaceutical research institute, he returned to academia in 1998 as a professor in the Department of Molecular Biology and the Woodrow Wilson School of Public and International Affairs at Princeton (now the Princeton School of Public and International Affairs). In 2002, the room where generations of medical students have attended basic science classes, Hope 110, was named after him.
Rosenberg was a visionary physician-scientist and leader who drew deep inspiration from his patients to inform his scientific pursuits with the aim of discovering the biochemical and genetic basis of human diseases to support the development of new therapies. He believed that work in the lab was just as important as that in the clinic. He took revelations from his patients’ family histories to lead a multidisciplinary team that gained fundamental insights into pediatric metabolic disorders and led to the development of gender-dependent treatments for these disorders.
His work uncovered the biochemical and genetic basis of life-threatening metabolic disorders that cause ketoacidosis or hyperammonemia and laid the foundation for the therapeutic treatments by modifying the diet or supplementing the enzymatic deficiencies. His work with Dr. For example, Margretta Seashore identified the biochemical basis of homocystinuria and showed how supplementing these patients with the cofactor vitamin B6 could reverse the disease, introducing the therapeutic potential of vitamins in metabolic disorders and personalized medicine.
His discoveries in academic medicine were recognized by the American Academy of Pediatrics’ Borden Award; the McKusick Leadership Award from the American Society for Human Genetics; and his election to both the Institute of Medicine and the National Academy of Sciences.
The multidisciplinary team led by Dr. Yale’s Rosenberg not only made fundamental discoveries in pediatrics and genetics, but also formed a cohort of outstanding physicians and scientists, including Anne Lilljeqvist, Roy Gravel, Ted Hsia, Wayne Fenton, Maurice Mahoney, Arthur Horwich, Gretta Seashore, Ira Mellman, Hunt Willard and Pamela Youngdahl-Turner, among others. Their discoveries have not only informed the basic science and treatment of patients, but also led to the development of some of the first prenatal diagnosis methods through biochemical analysis of metabolites in the amniotic fluid.
Rosenberg’s life was guided by the principle that physician-scientists are inculcated by their clinical experiences, and that their sick patients determine their quest for discoveries. The real prize is to discover something scientific that can be translated into understanding, comforting and occasionally healing a human being who is unique, genetically and clinically.
At Yale, his vision integrated clinical discovery and basic research with the goal of expanding our understanding of human biology, diagnosis and the development of new therapies. This served as a model for genetic discovery across the country. His vision is very much alive today, both in Yale’s Genetics Department and other genetics departments that have subsequently followed this model.