we're going to evolve. and there's going to be an ethical responsibility that we have to our kids to make them healthy. a whole generation that basically, we would betray if he didn't help them. basically that's cruel. >> what are the scary aspects of where this could go. >> i think it will get very hot in the next few years adding genomes for babies. >> where you'll be able to go in and order the perfect child? >> yes. we could potentially see an arms race among families -- >> to create the fastest, biggest, strongest, smartest? >> yeah. well, let's take out the correct copies of dna. >> this is incredible. >> so for me to live forever, i need to hack my dna. >> we will eventually be able to write the code, not only to fix our current mistakes but also fix mistakes as we age. that's going to be critical to living forever. there you go. >> correct copies of your dna. so if you want to access any of these sequences, you break the foil, add some liquid.