James Alexander Thomson, affectionately known as Jamie Thomson, is an American developmental biologist whose pioneering work in isolating and culturing non-human primate and human embryonic stem cells has made him one of the most prominent scientists in stem cell research. While growing up in Oak Park, Illinois, Thomson's rocket-scientist uncle inspired him to pursue science as a career. Born on 20 December 1958, Thomson entered the nearby University of Illinois Urbana-Champaign nineteen years later as a National Merit Scholar majoring in biophysics. He became fascinated with development via the encouragement and influence of Fred Meins, one of his undergraduate professors. After graduating as a Phi Beta Kappa scholar, Thomson took his interest in biology to the University of Pennsylvania where he earned two doctorate degrees: one in veterinary medicine, completed in 1985, and the other in molecular biology, completed in 1988. It was during his graduate years that Thomson began working with embryonic stem cells.

After becoming chief pathologist at the University of Wisconsin-Madison Wisconsin Regional Primate Center in 1995, James A. Thomson began his pioneering work in deriving embryonic stem cells from isolated embryos. That same year, Thomson published his first paper, "Isolation of a Primate Embryonic Stem Cell Line," in Proceedings of the National Academy of Sciences of the United States of America, detailing the first derivation of primate embryonic stem cells. In the following years, Thomson and his team of scientists - Joseph Itskovitz-Eldor, Sander S. Shapiro, Michelle A. Waknitz, Jennifer J. Swiergiel, Vivienne S. Marshall, and Jeffry M. Jones - advanced their work with embryonic stem cells, eventually isolating and culturing human embryonic stem cells. Their work with human embryos was reported in the 1998 Nature article "Embryonic Stem Cell Lines Derived from Human Blastocysts."