The Jacob Gershon-Cohen Professorship of Medical Science

The Professorship was established in 1989 through the bequest of Jacob Gershon-Cohen, MD (1899–1971), a prominent Philadelphia physician. Dr. Gershon-Cohen was an early proponent of the use of mammography for the early detection of breast cancer. He was a graduate of both Penn (1922) and the Perelman School of Medicine (1924).

Dr. Gershon-Cohen made his gift with the intent to create an environment conducive to the education of physicians of the Jewish faith. Impressed that the city of Philadelphia was among the first communities in America to “receive in the seventeenth-century Jewish colonists as full citizens and to give them religious freedom,” Dr. Gershon-Cohen wished to maintain that tradition by encouraging the medical education of young physicians.

Following residency training at the Hospital of the University of Pennsylvania, Dr. Gershon-Cohen opened his office in 1929 and quickly became known as a leader in radiology. Among his professional appointments, he was an Assistant Professor of Radiology at the Graduate School of Medicine of the University of Pennsylvania from 1941 to 1968. He served in the U.S. Navy during World War II.

A member of numerous medical organizations, Dr. Gershon-Cohen authored more than 400 papers. His many recognitions included the Alvarenga Prize of the College of Physicians of Philadelphia, the Gold Medal Award of the International College of Radiology, and the Clement Cleveland Award of the American Cancer Society for outstanding work in cancer control.

Current Chairholder
Blanton S. Tolbert, PhD

In 2022, Tolbert became the inaugural vice president of science leadership and culture at HHMI where he will develop and lead the new Center for the Advancement of Science Leadership and Culture. The mission of the Center is to intentionally integrate equity and inclusion into research culture. In this role, Tolbert directs a portfolio of current and new programs at the undergraduate and graduate level, an initiative to better equip HHMI scientists to provide culturally aware mentorship, a curriculum to grow scientists’ skills to maintain inclusive environments, and activities to develop strategic equity-centered initiatives and partnerships.

In July 2023, Tolbert became a Professor of Biochemistry and Biophysics at the University of Pennsylvania. Prior to this position, he was the Rudolph and Susan Rense Professor of Chemistry at Case Western Reserve University (CWRU). The research in the Tolbert group focuses on the biochemical mechanisms by which RNA viruses replicate within the cellular environment. His group leverages their fundamental understanding of the molecular biology of these viruses to identify novel targets for therapeutic intervention. The team has collaborated with colleagues to develop compounds with the potential to delay or halt the replication of SARS-CoV-2 and EV-A71. He will maintain his lab while serving as HHMI’s vice president of science leadership and culture. Prior to joining HHMI, Tolbert served as the inaugural vice dean of diversity, equity, and inclusive excellence for Case Western Reserve School of Medicine and as Case Comprehensive Cancer Center’s first associate director for diversity, equity, and inclusion. During his tenure, Tolbert developed initiatives to recruit individuals from backgrounds currently underrepresented in science into tenure-track faculty positions and to improve the experiences of faculty, staff, and students.

Throughout his professional career, he has consistently maintained a commitment to educating, training, and developing future scientific leaders. He believes in creating inclusive learning environments with an emphasis on encouraging students to develop critical thinking skills to comprehend foundational concepts. He has mentored dozens of trainees at all career stages ranging from high school through to postdoctoral fellows, with several being supported by diversity supplements and training grants. His trainees have gone on to PhD, MD/PhD programs; to become postdoctoral fellows; and they have accepted both academic and industrial positions. He has also served as the PI of an NSF-funded REU program in Chemistry. He was the co-PI and co-developer of the Interdisciplinary Research at the Interface of Health Science and the Environment (IRIHSE) research experience for undergraduates’ program. This program supported ten underrepresented students from the inner city of Cleveland (Emerging Scholars) and New Orleans (Posse Program) in two 5-week laboratory rotations spanning biomedical and environmental research. He was the acting Chairperson of the NIH Office of AIDS Research Advisory Council (OARAC) from 2018-2023. He chaired the OARAC Strategies to Support, Retain, and Expand the Pool of Early-Stage HIV Investigators panel discussion on May 5, 2021.

Tolbert earned a BS in chemistry at University of South Carolina and a PhD in biophysics and structural biology at University of Rochester. He was an HHMI postdoctoral fellow at University of Maryland, Baltimore County, with HHMI Investigator Michael Summers. In 2016, Tolbert received the inaugural Morton L. Mandel Award for Excellence in Research and Service from the CWRU chemistry department. In 2023, he was recognized by the International Society for Antiviral Research with the Diversity in Science and Excellence Award.

Previous Chairholders

• S. Walter Englander, PhD 1990–2004
• Gregory D. Van Duyne, PhD 2004-2023