It may not have made the lemur ill, but the retrovirus spread into the animal's testes (or perhaps its ovaries), and once there, it struck the jackpot: It slipped inside one of
the rare germ line cells that produce sperm and eggs.
For his part, Eric Lander from the Broad Institute said in a December 1 presentation at the summit that the need to employ
germ line editing would remain very, very
rare thanks to other already available reproductive technologies like in - vitro fertilization that could help most people.