" Inspired in part by the uncanny ability of viruses to splice new genetic information into the DNA of bacterial cells, the pioneers of this early gene therapy realized they could use viruses to deliver therapeutic genes to humans. The first reported attempts came in the late 1960s from Stanfield Rogers, an American physician who had been studying a wart-causing virus in rabbits, Shope papillomavirus. Rogers was particularly interested in one aspect of the Shope virus: It caused rabbits to overproduce arginase, an enzyme their bodies used to neutralize arginine, a harmful amino acid. The sick rabbits had much more arginase in their systems, and much less arginine, than healthy rabbits. What’s more, Rogers found that researchers who had worked with the virus also had lower-than-normal levels of arginine in their blood. Apparently these scientists had contracted the infections from the rabbits, and these infections had led to lasting changes in the researchers’ bodies as well. Rogers suspected that the Shope virus was ferrying a gene for heightened arginase production into cells. As he marveled at the virus’s ability to transfer its genetic information so effectively, he began to wonder if an engineered version could deliver other, useful genes. Many years later, Rogers would recall: “It was clear that we had uncovered a therapeutic agent in search of a disease!” Rogers didn’t have to wait long for a disease "

― Jennifer A. Doudna , A Crack in Creation: Gene Editing and the Unthinkable Power to Control Evolution