Katherine Parker Ponder, MD, professor emerita of medicine and of biochemistry and molecular biophysics at Washington University School of Medicine in St. Louis, died Saturday, July 18, 2026, of breast cancer. She was 69.
A highly accomplished physician-scientist, Ponder’s career spanned decades at WashU Medicine. She made significant advances in techniques to treat lysosomal storage diseases — rare, incurable, inherited metabolic diseases that collectively affect a significant swath of the world’s population.
Ponder was noted for improving treatments via gene therapy for such diseases. She was key in helping to develop more effective approaches by using retroviral vectors, a process by which RNA, a translator of genetic code, is used to insert therapeutic genes into cells.
“Dr. Ponder was a very successful, creative and incredibly dedicated physician-scientist who proved to be a wonderful mentor and a valued, longtime member of the hematology faculty,” said Victoria J. Fraser, MD, the Adolphus Busch Professor of Medicine and head of the John T. Milliken Department of Medicine. “She was amazingly courageous and resilient, and continued working on her research throughout most of her long and difficult battle with breast cancer. She will be deeply missed.”
Earlier in her career, Ponder studied hemophilia, a disease that prevents blood from clotting normally. She hypothesized that if a healthy copy of the missing gene could be placed into liver cells, the liver could make the needed clotting protein that could help stop dangerous bleeding.
Ponder applied the same idea to mucopolysaccharidoses, a group of inherited diseases in which the body cannot break down certain complex sugars. These substances collect inside cells and can cause damage to the brain, heart, bones and other organs. Her studies offered hope that similar gene-based treatments might one day help patients with rare diseases.
Ponder earned a bachelor’s degree in biology from Stanford University and a medical degree from WashU Medicine.
After completing residency training in Texas and Connecticut, she joined the faculty of WashU Medicine in 1990. She was appointed professor emerita in 2014.
Throughout her career, Ponder received numerous awards and participated in several professional societies and organizations. In 2016, she was honored with the Sonia Skarlatos Public Service Award from the American Society of Gene and Cell Therapy for her dedication to advancing the field.
Ponder had strong familial ties to WashU. Her parents — Mary Langston Parker, MD, and Charles Ward Parker, MD — were physicians, researchers and instructors at WashU Medicine. Ponder’s four siblings also graduated with WashU degrees.
She is survived by her husband, Jay William Ponder, PhD, a professor of chemistry, of biochemistry and molecular biophysics, and of biomedical engineering at WashU; her children, Kaitlin and Tyler (Anna Huang); and her siblings, Charlie, Christy and Sandy Parker Bigg.
A memorial service will take place at 1 p.m. Sept. 19, at First Congregational Church, 10 W. Lockwood Ave., Webster Groves, Mo.
In lieu of flowers, the family requested tribute gifts to the Katherine Parker Ponder Memorial Endowment. The fund will be used to support trainees and early-career faculty in the Division of Hematology, including research, education, travel to conferences or travel for other reasons, speaking engagements, and other uses that would support trainees and early-career faculty as they progress in their careers. Gifts to this fund will honor Katherine “Kathy” Parker Ponder, MD, recognizing her distinguished career as a physician-scientist, her deep commitment to advancing patient care and scientific discovery, and the many lives she touched through her generosity, mentorship and vibrant spirit.
Gifts can be made online at giving.wustl.edu/Ponder or by mailed check to “Washington University” and including “Katherine Parker Ponder Memorial Endowment” in the memo line or included note. Checks can be mailed to MSC 1082-414-2555, 7425 Forsyth Blvd., Clayton, Mo., 63105.
For more information on Ponder’s life, visit the family’s obituary.
Originally published on the WashU Medicine website