Biography: John Gearhart
Stem Cell Research

John Gearhart was born in Western Pennsylvania and lived on the family farm until he was six years old. When his father died, his mother placed him and one of his brothers in Girard College, an all-male orphanage where he remained until he graduated and entered Pennsylvania State University.

His memories of the family farm led him into horticulture. The study habits he had acquired in the orphanage served him well in the first year or two, but the sheltered environment of the orphanage had not prepared him for the temptations of life outside, and Gearhart saw many of his former classmates fall behind, unable to catch up. Then, as he puts it, he "fell in love with genetics." After earning his B. Sc. in Biological Science at Penn in 1964, he moved to the University of New Hampshire, where he was awarded an M. Sc. in Genetics in 1966. His work there confirmed him in his career path, and he applied to Cornell University, home of "the best genetics program in the country." His research had led him from the breeding of fruit trees, grain and flowers, to the genetics of the fruit fly and the mouse, to the study of human birth defects. He received his Ph.D. degree in Genetics, Development & Embryology in 1970.

Gearhart returned to Philadelphia and spent the next five years as an associate at the Institute for Cancer Research. For another five years, he was Associate Professor of Anatomy at the University of Maryland School of Medicine in Baltimore. In 1980, he joined the Johns Hopkins University School of Medicine.

Through all these years Gearhart had only occasional contact with his mother. His studies had led him far from the agricultural concerns of his family in Pennsylvania. When his mother became ill with cancer, she came to Johns Hopkins Hospital for treatment, and it was only then, in her last months of life, that the adult scientist felt he finally came to know the mother who had been forced to give him up so many years before.

John Gearhart is now the Director of Research and of the Developmental Genetics Division of the department of Gynecology and Obstetrics in the School of Medicine at Hopkins. He holds professorships in Physiology, Comparative Medicine, and Gynecology & Obstetrics in the School of Medicine, and in Biochemistry and Molecular Biology in the Bloomberg School of Public Health. Since 1990 he has been a member of the Medical Genetics Center and the Center for Reproductive Biology.

Much of his research career has focused on the way genes regulate the formation of tissues and embryos. For the last 20 years he has attempted to determine the exact causes of mental retardation and other birth defects in Down's Syndrome. The isolation of the stem cells of mice emboldened him to attack one of the most difficult challenges of all, the isolation and culturing of human stem cells, the undifferentiated cells from which all the multifarious tissues of our bodies derive.

Gearhart's team successfully identified and isolated the stem cells and has maintained them in a nutritive environment where they continue reproducing without differentiating. The achievement has profound implications for drug development and transplant therapy, and raises the possibility of growing human tissues in the laboratory to replenish failing organs.

On November 10, 1998, John Gearhart reported his stem cell findings in the Proceedings of the National Academy of Sciences. Almost simultaneously, a team led by Dr. James Thomson at the University of Wisconsin also succeed in culturing human stem cells. While Gearhart's team in Baltimore obtained its stem cells from human fetal tissue, the Wisconsin team worked with cells taken from human embryos created in vitro, a course of research which was denied federal funding for many years. Although Gearhart's work with fetal tissue was never subject to the federal research ban, and is privately funded in any event, he has been outspoken in his advocacy of federal funding for further embryonic stem cell research. Under the terms of a ban imposed by President George W. Bush, federal funding for embryonic stem cell research was only available for the lines of existing cell cultures, not for obtaining further samples from discarded embryos. This ban was later lifted by an executive order of President Barack Obama, only to be reinstated by a federal court order.

The possible future benefits of human stem cell research, he believes, warrant the support of the national government. Further, he has stated, the oversight that comes with government funding and will be helpful in answering the ethical concerns of the public. As Gearhart himself says, "...scientific responsibility includes the obligation to make public any social implications of the research and its technological applications."

In 2008, John Gearhart was named a Penn Integrates Knowledge Professor at the University of Pennsylvania and was appointed Director of the University's Institute for Regenerative Medicine.