Ralph L. Brinster


Ralph Lawrence Brinster is an American geneticist and Richard King Mellon Professor of Reproductive Physiology at the School of Veterinary Medicine, University of Pennsylvania.

Early life and education

Ralph L. Brinster grew up in a small farm in Cedar Grove, New Jersey where his parents raised purebred animals. He studied animal science as an undergraduate at the Cook School of Agriculture, Rutgers University, New Brunswick, and completed his B.S. in 1953. He was an officer in the United States Air Force and served during the Korean War. He returned from military service and earned his V.M.D. and his Ph.D. in Physiology from the University of Pennsylvania.

Research impact

Ralph Brinster is acknowledged as one of the seminal founders of the field of mammalian transgenesis. He is known throughout the scientific community for his revolutionary research in embryonic-cell differentiation, developmental mechanisms of gene control, and stem cell physiology.
During the 1960s, Brinster pioneered the development of techniques to manipulate mouse embryos—his techniques have made the mouse the major genetic model for understanding the basis of human biology and disease. His research has provided the experimental foundation for progress in germline genetic modification in a range of species, which has generated a revolution in biology, medicine, and agriculture. His h-index, a commonly used calculation estimating research impact, is 120, which ranks among the highest in the life sciences.

Research history

While a Ph.D. candidate in the 1960s, Brinster developed the first reliable in vitro culture system for early mammalian embryos. These techniques have been conserved to the present day and form the foundation for all experimentation with the mammalian embryo - including transgenic, embryonic stem cell, human and mammalian in vitro fertilization, mammalian cloning, and knockout technology. This "Brinster Method" of embryo manipulation is so ubiquitous in modern biology that other scientists rarely cite the work in current publications.
Brinster first showed that it was possible to colonize a mouse blastocyst with stem cells from older embryos. Moreover, Brinster first demonstrated that foreign teratocarcinoma cells could combine with native blastocyst cells to form adult "chimeric" mice, demonstrating the feasibility of this approach to change the genetic character of mice. This discovery stimulated the search for embryonic stem cells and ultimately led to the development of the "knock-out mouse" by other teams. He was the first scientist to microinject fertilized eggs with RNA and DNA, and was at the forefront of the field in applying these microinjection methods to generate transgenic mice.
Brinster and longtime collaborator Richard Palmiter pioneered techniques to transfer foreign genes into mammals, and they utilized these methods to elucidate the activity and function of genes. They developed the first "transgenic mice", in fact the two established the term "transgenic" in the scientific literature in a foundational paper, and their seminal experiments catalyzed a worldwide revolution in genetic engineering in the 1980s. Transgenic mice are now used every day in thousands of laboratories around the world to investigate everything from cancer biology and cardiovascular disease to hair loss and abnormal behavior.
Their experiments showed that new genes could be, for the first time, introduced into the mammalian germline with the potential to increase disease resistance, enhance growth, and produce vital proteins like blood-clotting factors needed by hemophiliacs. In addition, they provided the first proof of expression of transgenes, the first example of cancer arising from a transgene, and the first proof of the targeted integration of DNA by egg injection.
Each of these three revolutionary discoveries have themselves launched entire fields of scientific inquiry.
Together, Palmiter and Brinster developed many of the first animal models of human disease throughout the 1980s. Their partnership also yielded the first transgenic rabbits, sheep, and pigs. This transcontinental collaboration constructed a body of work that formed the foundation for a generation of scientific progress in genetic modification via transgenesis, homologous recombination or "knock-out" techniques, and cloning.
In recent years, Brinster has continued to advance the field of stem cell biology, having made a series of catalyzing, transformational discoveries utilizing male germ line stem cells.

Awards and honors

The widely acclaimed Zadie Smith novel "White Teeth" features prominently a genetically modified mouse "Futuremouse", based loosely on the transgenic experiments of Palmiter and Brinster in the 1980s.
In 2017, Dr. Brinster was depicted in his laboratory in The Observer by portrait artist Mary Whyte. Whyte was recently presented the Portrait Society of America Gold Medal in honor of "a lifelong dedication to excellence, as well as in recognition of a distinguished body of work that serves to foster and enhance fine art portraiture and figurative works in America."