“We’re going to see a stream of edited animals coming through because it’s so easy,” said Bruce Whitelaw, a professor of animal biotechnology at the Roslin Institute at the University of Edinburgh. “It’s going to change the societal question from, ‘If we could do it, would we want it?’ to, ‘Next year we will have it; will we allow it?’ ”
Animal breeders have for centuries scoured species for desirable traits and combined them the old-fashioned way, by selective mating. But that process can take decades to achieve a particular goal, like cows that are both resistant to disease and produce a lot of milk. And until recently, genetic engineering techniques used to manipulate DNA had been so imprecise as to make them too expensive and difficult to perform in many animals.
But the new techniques, collectively called “gene editing” to reflect the relative ease of their use, have made all manner of previously impossible or impractical goals sufficiently fast and cheap for many to find worth pursuing. Using enzymes that can be directed to cut DNA at specific locations, they allow scientists to remove and replace bits of genetic code more or less on demand. “It’s like a find-replace function in the genome of these animals,” said Scott Fahrenkrug, the chief executive of Recombinetics, based in St. Paul. “It allows us to find the natural variation that exists across a species and quickly bring it under one hood.”