PHILADELPHIA – Ralph L. Brinster, professor of reproductive physiology at the University of Pennsylvania School of Veterinary Medicine, has been selected as a recipient of the 2002-03 Wolf Prize in Medicine. The Wolf Prize jury cited him "for the development of procedures to manipulate mouse ova and embryos, which has enabled transgenesis and its applications in mice."

Brinster shares the prize with Oliver Smithies of the University of North Carolina and Mario R. Capecchi of the University of Utah. The three researchers were honored for developing techniques "for introducing and modifying individual genes within mouse eggs and embryos," the prize jury said.

Brinster, a veterinarian, developed a culture system to maintain mouse and other mammalian eggs in vitro and identified many fundamental characteristics of egg culture. This was essential for the generation of transgenic animals. Brinster first showed that it was possible to colonize a mouse blastocyst with stem cells from older embryos. He was the first to microinject fertilized eggs with RNA and was a pioneer in the field in applying these microinjection methods to generate transgenic mice.

The Wolf Foundation was established in Israel by the late Ricardo Wolf who served as Cuba's ambassador to Israel. The Wolf Prize in Medicine has been awarded since 1978 "for achievements in the interest of mankind and friendly relations among peoples, irrespective of nationality, race, color, religion, sex or political view." There are also prizes in agriculture, chemistry, mathematics, physics and the arts.

The 2002-03 Wolf Prizes will be conferred by Israeli President Moshe Katsav in Jerusalem May 11.