Dr Ralph Brinster is a pioneer in the development of techniques for manipulating the cellular and genetic composition of early mouse embryos. These techniques have made the mouse the major genetic model for understanding the basis of human biology and disease. He began his work by showing how mouse embryos could be cultured in a Petri dish in a simple culture medium and then showing how cells could be added to such embryos to make animals of mixed cell origins or chimeras. This work was a key enabler of targeted mutagenesis in embryonic stem cells, which has revolutionized our ability to understand gene function in mammals. He is acknowledged as the founder of the field of mammalian transgenesis, with its applications to human disease models and biotechnology. In recent years he has developed new models of germline manipulation using sperm progenitor cell transplants. In all these studies, Dr Brinster has been an innovator, a perfectionist and a forward thinker, understanding clearly the need to develop enabling technologies to pursue novel biological questions. His range of contributions is unmatched in the field.

Dr Brinster grew up on a small farm in Cedar Grove, New Jersey, where some of his early experiences with animals included, as a teenager, running a small poultry business, which helped finance his studies in veterinary medicine. After completing his DVM and Ph.D. studies at the University of Pennsylvania, he joined the faculty of the School of Veterinary Medicine there in 1960. He remains on faculty today as Richard King Mellon Professor of Reproductive Physiology in the School of Veterinary Medicine. He is a member of the National Academy and the Institute of Medicine and has received many awards and honours including the Wolf Prize, 2003 and the first March of Dimes Prize in Developmental Biology in 1996..