Dr. Robert Lanza has always been something of a renegade. It came as no surprise when he decided to lead the charge into medicine’s most controversial turf -- the creation of cloned embryos for therapy and the engineering of spare human parts.

Lanza has long believed in the value of therapeutic cloning. He did his early work with South African heart transplant pioneer Christiaan Barnard, and Lanza understood that the barrier to tissue transfer was rejection by the recipient. But embryonic clones, the source of an endless supply of stem cells imprinted with one’s personal DNA, could potentially avoid this problem.

However, for almost 20 years, government policy has kept Lanza’s innovations literally on ice. He has been called a murderer for tampering with embryos, and personal threats were so common at one point that he believed he would be killed.

Click the link below to read a fascinating interview that Discover Magazine senior editor Pamela Weintraub recently conducted with Lanza.