[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:01.07,0:00:03.53,Default,,0000,0000,0000,,So this is a talk about gene drives,
Dialogue: 0,0:00:03.53,0:00:06.80,Default,,0000,0000,0000,,but I'm going to start by \Ntelling you a brief story.
Dialogue: 0,0:00:06.80,0:00:09.87,Default,,0000,0000,0000,,20 years ago, a biologist\Nnamed Anthony James
Dialogue: 0,0:00:09.87,0:00:12.21,Default,,0000,0000,0000,,got obsessed with the idea\Nof making mosquitos
Dialogue: 0,0:00:12.21,0:00:15.86,Default,,0000,0000,0000,,that didn't transmit malaria.
Dialogue: 0,0:00:15.86,0:00:20.80,Default,,0000,0000,0000,,It was a great idea, and pretty\Nmuch a complete failure.
Dialogue: 0,0:00:20.80,0:00:23.43,Default,,0000,0000,0000,,For one thing, it turned \Nout to be really hard
Dialogue: 0,0:00:23.43,0:00:26.47,Default,,0000,0000,0000,,to make a malaria resistant mosquito.
Dialogue: 0,0:00:26.47,0:00:29.54,Default,,0000,0000,0000,,James managed it, finally,\Njust a few years ago
Dialogue: 0,0:00:29.54,0:00:31.90,Default,,0000,0000,0000,,by adding some genes\Nthat make it impossible
Dialogue: 0,0:00:31.90,0:00:35.76,Default,,0000,0000,0000,,for the malaria parasite\Nto survive inside the mosquito.
Dialogue: 0,0:00:35.76,0:00:38.22,Default,,0000,0000,0000,,But that just created another problem.
Dialogue: 0,0:00:38.22,0:00:41.05,Default,,0000,0000,0000,,Now that you've got a \Nmalaria-resistant mosquito,
Dialogue: 0,0:00:41.05,0:00:46.32,Default,,0000,0000,0000,,how do you get it to replace\Nall the malaria-carrying mosquitos?
Dialogue: 0,0:00:46.32,0:00:48.13,Default,,0000,0000,0000,,There are a couple options,
Dialogue: 0,0:00:48.13,0:00:50.01,Default,,0000,0000,0000,,but plan A was basically to breed up\N
Dialogue: 0,0:00:50.01,0:00:52.46,Default,,0000,0000,0000,,a bunch of the new \Ngenetically-engineered mosquitos
Dialogue: 0,0:00:52.46,0:00:54.26,Default,,0000,0000,0000,,release them into the wild,
Dialogue: 0,0:00:54.26,0:00:56.67,Default,,0000,0000,0000,,and hope that they pass on their genes.
Dialogue: 0,0:00:56.67,0:00:58.81,Default,,0000,0000,0000,,The problem was that you'd \Nhave to release
Dialogue: 0,0:00:58.81,0:01:03.14,Default,,0000,0000,0000,,literally 10x the number of native\Nmosquitos to work.
Dialogue: 0,0:01:03.14,0:01:05.25,Default,,0000,0000,0000,,So in a village with 10,000 mosquitos,
Dialogue: 0,0:01:05.25,0:01:08.50,Default,,0000,0000,0000,,you release an extra 100,000.
Dialogue: 0,0:01:08.50,0:01:11.00,Default,,0000,0000,0000,,As you might guess, this was not\Na very popular strategy
Dialogue: 0,0:01:11.00,0:01:12.51,Default,,0000,0000,0000,,with the villagers.
Dialogue: 0,0:01:12.51,0:01:15.14,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:01:15.14,0:01:18.83,Default,,0000,0000,0000,,Then, last January, Anthony James\Ngot an email
Dialogue: 0,0:01:18.83,0:01:21.64,Default,,0000,0000,0000,,from a biologist named \NEthan Bier.
Dialogue: 0,0:01:21.64,0:01:24.27,Default,,0000,0000,0000,,Bier said that he and his grad student,\NValentino Gantz,
Dialogue: 0,0:01:24.27,0:01:26.89,Default,,0000,0000,0000,,had stumbled on a tool that could \Nnot only guarentee
Dialogue: 0,0:01:26.89,0:01:30.16,Default,,0000,0000,0000,,that a particular genetic trait\Nwould be inherited,
Dialogue: 0,0:01:30.16,0:01:32.35,Default,,0000,0000,0000,,but that it would spread\Nincredibly quickly.
Dialogue: 0,0:01:32.35,0:01:35.22,Default,,0000,0000,0000,,If they were right, it would basically\Nsolve the problem
Dialogue: 0,0:01:35.22,0:01:38.75,Default,,0000,0000,0000,,that he and James had been\Nworking on for 20 years.
Dialogue: 0,0:01:38.75,0:01:41.56,Default,,0000,0000,0000,,As a test, they engineered\Ntwo mosquitos
Dialogue: 0,0:01:41.56,0:01:43.26,Default,,0000,0000,0000,,to carry the anti-malaria gene
Dialogue: 0,0:01:43.26,0:01:45.56,Default,,0000,0000,0000,,and also this new tool,\Na gene drive,
Dialogue: 0,0:01:45.56,0:01:47.51,Default,,0000,0000,0000,,which I'll explain in a minute.
Dialogue: 0,0:01:47.51,0:01:49.71,Default,,0000,0000,0000,,Finally, they set it up so that\Nany mosquitos
Dialogue: 0,0:01:49.71,0:01:51.82,Default,,0000,0000,0000,,that had inherited the\Nanti-malaria gene
Dialogue: 0,0:01:51.82,0:01:55.58,Default,,0000,0000,0000,,wouldn't have the usual white eyes,\Nbut would instead have red eyes.
Dialogue: 0,0:01:55.58,0:01:58.28,Default,,0000,0000,0000,,That was pretty much just \Nfor convenience
Dialogue: 0,0:01:58.28,0:02:02.41,Default,,0000,0000,0000,,so they could tell just at a glance\Nwhich was which.
Dialogue: 0,0:02:02.41,0:02:05.15,Default,,0000,0000,0000,,So they took their two \Nanti-malarial, red-eyed mosquitos
Dialogue: 0,0:02:05.15,0:02:07.85,Default,,0000,0000,0000,,and put them in a box with 30\Nordinary white-eyed ones
Dialogue: 0,0:02:07.85,0:02:09.80,Default,,0000,0000,0000,,and let them breed.
Dialogue: 0,0:02:09.80,0:02:14.53,Default,,0000,0000,0000,,In two generations, those had \Nproduced 38,000 grandchildren.
Dialogue: 0,0:02:14.53,0:02:16.97,Default,,0000,0000,0000,,That is not the surprising part.
Dialogue: 0,0:02:16.97,0:02:18.92,Default,,0000,0000,0000,,This is the surprising part:
Dialogue: 0,0:02:18.92,0:02:21.59,Default,,0000,0000,0000,,Given that you started with just\Ntwo red-eyed mosquitos
Dialogue: 0,0:02:21.59,0:02:23.17,Default,,0000,0000,0000,,and 30 white-eyed ones,
Dialogue: 0,0:02:23.17,0:02:26.72,Default,,0000,0000,0000,,you expect mostly white-eyed\Ndescendents.
Dialogue: 0,0:02:26.72,0:02:29.79,Default,,0000,0000,0000,,Instead, when James opened the box,
Dialogue: 0,0:02:29.79,0:02:33.60,Default,,0000,0000,0000,,all 38,000 mosquitos had red eyes.
Dialogue: 0,0:02:33.60,0:02:35.82,Default,,0000,0000,0000,,When I asked Ethan Bier\Nabout this moment,
Dialogue: 0,0:02:35.82,0:02:39.72,Default,,0000,0000,0000,,he became so excited, tht he was\Nliterally shouting into the phone.
Dialogue: 0,0:02:39.72,0:02:42.07,Default,,0000,0000,0000,,That's because getting only\Nred-eyed mosquitos
Dialogue: 0,0:02:42.07,0:02:45.04,Default,,0000,0000,0000,,violates a rule that is the\Nabsolute cornerstone of biology,
Dialogue: 0,0:02:45.04,0:02:46.91,Default,,0000,0000,0000,,Mendelian genetics.
Dialogue: 0,0:02:46.91,0:02:49.20,Default,,0000,0000,0000,,I'll keep this quick, \Nbut Mendelian genetics
Dialogue: 0,0:02:49.20,0:02:50.87,Default,,0000,0000,0000,,says when a male and a female mate,
Dialogue: 0,0:02:50.87,0:02:53.75,Default,,0000,0000,0000,,their baby inherits half of its\NDNA from each parent.
Dialogue: 0,0:02:53.75,0:02:57.35,Default,,0000,0000,0000,,So if our original mosquito was aa\Nand our new mosquito is aB,
Dialogue: 0,0:02:57.35,0:02:59.14,Default,,0000,0000,0000,,where B is the anti-malarial gene,
Dialogue: 0,0:02:59.14,0:03:01.42,Default,,0000,0000,0000,,the babies should come out\Nin four permutations:
Dialogue: 0,0:03:01.42,0:03:05.13,Default,,0000,0000,0000,,aa, aB, aa, Ba.
Dialogue: 0,0:03:05.13,0:03:07.20,Default,,0000,0000,0000,,Instead, with the new gene drive,
Dialogue: 0,0:03:07.20,0:03:10.12,Default,,0000,0000,0000,,they all came out aB.
Dialogue: 0,0:03:10.12,0:03:12.72,Default,,0000,0000,0000,,Biologically, that shouldn't\Neven be possible.
Dialogue: 0,0:03:12.72,0:03:14.91,Default,,0000,0000,0000,,So what happened?
Dialogue: 0,0:03:14.91,0:03:17.20,Default,,0000,0000,0000,,The first thing that happened\Nwas the arrival
Dialogue: 0,0:03:17.20,0:03:20.06,Default,,0000,0000,0000,,of a gene-editing tool\Nknown as CRISPR in 2012.
Dialogue: 0,0:03:20.06,0:03:22.54,Default,,0000,0000,0000,,Many of you have probably heard\Nabout CRISPR,
Dialogue: 0,0:03:22.54,0:03:25.83,Default,,0000,0000,0000,,so I'll just say briefly that CRISPR\Nis a tool that allows researchers
Dialogue: 0,0:03:25.83,0:03:29.04,Default,,0000,0000,0000,,to edit genes very precisely,\Neasily and quickly.
Dialogue: 0,0:03:29.04,0:03:32.71,Default,,0000,0000,0000,,It does this by harnessing a mechanism\Nthat already existed in bacteria.
Dialogue: 0,0:03:32.71,0:03:35.41,Default,,0000,0000,0000,,Basically, there's a protein\Nthat acts like a scissors
Dialogue: 0,0:03:35.41,0:03:36.88,Default,,0000,0000,0000,,and cuts the DNA,
Dialogue: 0,0:03:36.88,0:03:39.43,Default,,0000,0000,0000,,and there's an RNA molecule\Nthat directs the scissors
Dialogue: 0,0:03:39.43,0:03:41.24,Default,,0000,0000,0000,,to any point on the genome you want.
Dialogue: 0,0:03:41.24,0:03:44.65,Default,,0000,0000,0000,,The result is basically a word processor\Nword processor for genes.
Dialogue: 0,0:03:44.65,0:03:47.14,Default,,0000,0000,0000,,You can take an entire gene out,\Nput one in,
Dialogue: 0,0:03:47.14,0:03:49.94,Default,,0000,0000,0000,,or even edit just a single letter\Nwithin a gene.
Dialogue: 0,0:03:49.94,0:03:53.54,Default,,0000,0000,0000,,And you can do it in nearly any species.
Dialogue: 0,0:03:53.54,0:03:55.64,Default,,0000,0000,0000,,Okay, remember how I said \Nthat gene drives
Dialogue: 0,0:03:55.64,0:03:57.91,Default,,0000,0000,0000,,originally had two problems?
Dialogue: 0,0:03:57.91,0:04:01.14,Default,,0000,0000,0000,,The first was that it was hard\Nto engineer a mosquito
Dialogue: 0,0:04:01.14,0:04:02.62,Default,,0000,0000,0000,,to be malaria resistant.
Dialogue: 0,0:04:02.62,0:04:05.36,Default,,0000,0000,0000,,That's basically gone now,\Nthanks to CRISPR.
Dialogue: 0,0:04:05.36,0:04:07.55,Default,,0000,0000,0000,,But the other problem was \Nlogistical.
Dialogue: 0,0:04:07.55,0:04:10.40,Default,,0000,0000,0000,,How do you get your trait to spread?
Dialogue: 0,0:04:10.40,0:04:13.16,Default,,0000,0000,0000,,This is where it gets clever.
Dialogue: 0,0:04:13.16,0:04:16.45,Default,,0000,0000,0000,,A couple years ago, a biologist\Nat Harvard named Kevin Esvelt
Dialogue: 0,0:04:16.45,0:04:18.99,Default,,0000,0000,0000,,wondered what would happen\Nif you made it so that
Dialogue: 0,0:04:18.99,0:04:21.80,Default,,0000,0000,0000,,CRISPR inserted not only\Nyour new gene,
Dialogue: 0,0:04:21.80,0:04:25.45,Default,,0000,0000,0000,,but also the machinery \Nthat does the cutting and pasting.
Dialogue: 0,0:04:25.45,0:04:30.18,Default,,0000,0000,0000,,In other words, what if CRISPR\Nalso copy and pasted itself.
Dialogue: 0,0:04:30.18,0:04:34.71,Default,,0000,0000,0000,,You'd end up with a perpetual\Nmotion machine for gene editing.
Dialogue: 0,0:04:34.71,0:04:37.27,Default,,0000,0000,0000,,And that's exactly what happened.
Dialogue: 0,0:04:37.27,0:04:40.08,Default,,0000,0000,0000,,This CRISPR gene drive\Nthat Esvelt created
Dialogue: 0,0:04:40.08,0:04:43.61,Default,,0000,0000,0000,,not only guarantees that a trait \Nwill get passed on,
Dialogue: 0,0:04:43.61,0:04:46.07,Default,,0000,0000,0000,,but if its used in the germline cell,
Dialogue: 0,0:04:46.07,0:04:48.67,Default,,0000,0000,0000,,it will automatically copy and paste\Nyour new gene
Dialogue: 0,0:04:48.67,0:04:51.99,Default,,0000,0000,0000,,into both chromosomes of every\Nsingle individual.
Dialogue: 0,0:04:51.99,0:04:54.45,Default,,0000,0000,0000,,It's like a global search and replace,
Dialogue: 0,0:04:54.45,0:04:58.67,Default,,0000,0000,0000,,or in science terms, it makes\Na heterozygous trait homozygous.
Dialogue: 0,0:04:58.67,0:05:01.93,Default,,0000,0000,0000,,So, what does this mean?
Dialogue: 0,0:05:01.93,0:05:04.57,Default,,0000,0000,0000,,For one thing, it means we have\Na very powerful,
Dialogue: 0,0:05:04.57,0:05:08.58,Default,,0000,0000,0000,,but also somewhat alarming new tool.
Dialogue: 0,0:05:08.58,0:05:11.59,Default,,0000,0000,0000,,Up until now, the fact that gene drives\Ndidn't work very well
Dialogue: 0,0:05:11.59,0:05:13.27,Default,,0000,0000,0000,,was actually kind of a relief.
Dialogue: 0,0:05:13.27,0:05:15.90,Default,,0000,0000,0000,,Normally when we mess around\Nwith an organisms's genes,
Dialogue: 0,0:05:15.90,0:05:18.26,Default,,0000,0000,0000,,we make that thing \Nless evolutionarily fit.
Dialogue: 0,0:05:18.26,0:05:21.26,Default,,0000,0000,0000,,So biologists can make all the mutant\Nfruit flies they want
Dialogue: 0,0:05:21.26,0:05:22.50,Default,,0000,0000,0000,,without worrying about it.
Dialogue: 0,0:05:22.50,0:05:27.00,Default,,0000,0000,0000,,If some escape, natural selection\Njust takes care of it.
Dialogue: 0,0:05:27.00,0:05:30.30,Default,,0000,0000,0000,,What's remarkable and powerful\Nand frightening about gene drives
Dialogue: 0,0:05:30.30,0:05:32.86,Default,,0000,0000,0000,,is that that will no longer be true.
Dialogue: 0,0:05:32.86,0:05:36.94,Default,,0000,0000,0000,,Assuming that your trait does not\Nhave a big evolutionary handicap,
Dialogue: 0,0:05:36.94,0:05:39.01,Default,,0000,0000,0000,,like a mosquito that can't fly,
Dialogue: 0,0:05:39.01,0:05:42.49,Default,,0000,0000,0000,,the CRISPR-based gene drive\Nwill spread the change relentlessly
Dialogue: 0,0:05:42.49,0:05:47.32,Default,,0000,0000,0000,,until it is in every single individual\Nin the population.
Dialogue: 0,0:05:47.32,0:05:50.18,Default,,0000,0000,0000,,Now, it isn't easy to make\Na gene drive that works that well,
Dialogue: 0,0:05:50.18,0:05:53.57,Default,,0000,0000,0000,,but James and Esvelt think\Nthat we can.
Dialogue: 0,0:05:53.57,0:05:57.47,Default,,0000,0000,0000,,The good news is that this opens\Nthe door to some remarkable things.
Dialogue: 0,0:05:57.47,0:06:00.12,Default,,0000,0000,0000,,If you put an anti-malarial gene drive\Nin just 1 percent
Dialogue: 0,0:06:00.12,0:06:03.14,Default,,0000,0000,0000,,of anopheles mosquitos,\Nthe species that transmits malaria.
Dialogue: 0,0:06:03.14,0:06:06.50,Default,,0000,0000,0000,,Researchers estimate that it would\Nspread to the entire population
Dialogue: 0,0:06:06.50,0:06:08.41,Default,,0000,0000,0000,,in a year.
Dialogue: 0,0:06:08.41,0:06:11.07,Default,,0000,0000,0000,,So in a year, you could virtually \Neliminate malaria.
Dialogue: 0,0:06:11.07,0:06:14.35,Default,,0000,0000,0000,,In practice, we're still a few years out\Nfrom being able to do that,
Dialogue: 0,0:06:14.35,0:06:18.34,Default,,0000,0000,0000,,but sitll, a 1,000 children a day\Ndie of malaria.
Dialogue: 0,0:06:18.34,0:06:21.29,Default,,0000,0000,0000,,In a year, that number could be\Nalmost zero.
Dialogue: 0,0:06:21.29,0:06:25.43,Default,,0000,0000,0000,,The same goes for dengue fever,\Nchicken genuang (?), yellow fever.
Dialogue: 0,0:06:25.43,0:06:27.47,Default,,0000,0000,0000,,And it gets better.
Dialogue: 0,0:06:27.47,0:06:30.02,Default,,0000,0000,0000,,Say you want to get rid \Nof an invasive species,
Dialogue: 0,0:06:30.02,0:06:32.67,Default,,0000,0000,0000,,like get Asian Carp out of\NThe Great Lakes.
Dialogue: 0,0:06:32.67,0:06:34.69,Default,,0000,0000,0000,,All you have to do is release \Na gene drive
Dialogue: 0,0:06:34.69,0:06:37.57,Default,,0000,0000,0000,,that makes the fish produce\Nonly male offspring.
Dialogue: 0,0:06:37.57,0:06:41.42,Default,,0000,0000,0000,,In a few generations, there'll be\Nno females left, no more carp.
Dialogue: 0,0:06:41.42,0:06:44.16,Default,,0000,0000,0000,,In theory, this means that we \Ncould restore hundreds
Dialogue: 0,0:06:44.16,0:06:47.60,Default,,0000,0000,0000,,of native species that have been\Npushed to the brink.
Dialogue: 0,0:06:47.60,0:06:50.97,Default,,0000,0000,0000,,Okay, that's the good news,
Dialogue: 0,0:06:50.97,0:06:53.31,Default,,0000,0000,0000,,this is the bad news.
Dialogue: 0,0:06:53.31,0:06:55.38,Default,,0000,0000,0000,,Gene drives are so effective,
Dialogue: 0,0:06:55.38,0:06:59.23,Default,,0000,0000,0000,,that even an accidental release \Ncould change an entire species,
Dialogue: 0,0:06:59.23,0:07:01.44,Default,,0000,0000,0000,,and often very quickly.
Dialogue: 0,0:07:01.44,0:07:03.53,Default,,0000,0000,0000,,Anthony James took good precautions.
Dialogue: 0,0:07:03.53,0:07:05.75,Default,,0000,0000,0000,,He breed his mosquitos in\Na bio-containment lab
Dialogue: 0,0:07:05.75,0:07:08.43,Default,,0000,0000,0000,,and he also used a species\Nthat's not native to the US
Dialogue: 0,0:07:08.43,0:07:10.18,Default,,0000,0000,0000,,so that even if some did escape,
Dialogue: 0,0:07:10.18,0:07:11.49,Default,,0000,0000,0000,,they'd just die off,
Dialogue: 0,0:07:11.49,0:07:13.52,Default,,0000,0000,0000,,there'd be nothing for them\Nto mate with.
Dialogue: 0,0:07:13.52,0:07:15.65,Default,,0000,0000,0000,,But it's also true that if \Na dozen Asian Carp
Dialogue: 0,0:07:15.65,0:07:19.48,Default,,0000,0000,0000,,with the all-male gene drive accidentally\Ngot carried from The Great Lakes
Dialogue: 0,0:07:19.48,0:07:20.97,Default,,0000,0000,0000,,back to Asia,
Dialogue: 0,0:07:20.97,0:07:25.52,Default,,0000,0000,0000,,they could potentially wipe out \Nthe native Asian Carp population.
Dialogue: 0,0:07:25.52,0:07:29.05,Default,,0000,0000,0000,,And that's not so unlikely, given\Nhow connected our world is.
Dialogue: 0,0:07:29.05,0:07:32.23,Default,,0000,0000,0000,,In fact, it's why we have \Nan invasive species problem.
Dialogue: 0,0:07:32.23,0:07:33.65,Default,,0000,0000,0000,,And that's fish.
Dialogue: 0,0:07:33.65,0:07:37.83,Default,,0000,0000,0000,,Things like mosquitos and fruit flies,\Nthere's literally no way to contain them.
Dialogue: 0,0:07:37.83,0:07:41.98,Default,,0000,0000,0000,,They cross borders and oceans\Nall the time.
Dialogue: 0,0:07:41.98,0:07:44.47,Default,,0000,0000,0000,,Okay, the other piece \Nof bad news is that
Dialogue: 0,0:07:44.47,0:07:48.14,Default,,0000,0000,0000,,a gene drive might not stay confined\Nto what we call the target species.
Dialogue: 0,0:07:48.14,0:07:50.08,Default,,0000,0000,0000,,That's because of gene flow,
Dialogue: 0,0:07:50.08,0:07:52.87,Default,,0000,0000,0000,,which is a fancy way of saying\Nthat neighboring species
Dialogue: 0,0:07:52.87,0:07:54.10,Default,,0000,0000,0000,,sometimes inter-breed.
Dialogue: 0,0:07:54.10,0:07:57.15,Default,,0000,0000,0000,,If that happens, it's possible\Na gene drive could cross over,
Dialogue: 0,0:07:57.15,0:07:59.86,Default,,0000,0000,0000,,like Asian Carp could infect\Nsome other kind of Carp.
Dialogue: 0,0:07:59.86,0:08:03.44,Default,,0000,0000,0000,,That's not so bad if your drive\Njust promotes a trait, like eye color.
Dialogue: 0,0:08:03.44,0:08:06.37,Default,,0000,0000,0000,,In fact, there's a decent chance that\Nwe'll see a wave
Dialogue: 0,0:08:06.37,0:08:09.61,Default,,0000,0000,0000,,of very weird fruit flies \Nin the near future.
Dialogue: 0,0:08:09.61,0:08:12.35,Default,,0000,0000,0000,,But it could be a disaster\Nif your drive is deigned
Dialogue: 0,0:08:12.35,0:08:14.63,Default,,0000,0000,0000,,to eliminate the species entirely.
Dialogue: 0,0:08:14.63,0:08:17.90,Default,,0000,0000,0000,,The last worrisome thing is that\Nthe technology to do this,
Dialogue: 0,0:08:17.90,0:08:21.62,Default,,0000,0000,0000,,to genetically engineer an organism\Nand include a gene drive,
Dialogue: 0,0:08:21.62,0:08:25.54,Default,,0000,0000,0000,,is something that basically any lab\Nin the world can do.
Dialogue: 0,0:08:25.54,0:08:27.42,Default,,0000,0000,0000,,An undergraduate can do it.
Dialogue: 0,0:08:27.42,0:08:32.16,Default,,0000,0000,0000,,A talented high schooler\Nwith some equipment can do it.
Dialogue: 0,0:08:32.16,0:08:35.53,Default,,0000,0000,0000,,Now I'm guessing that \Nthis sounds terrifying.
Dialogue: 0,0:08:35.53,0:08:40.50,Default,,0000,0000,0000,,Interestingly though, nearly \Nevery scientist I talk to
Dialogue: 0,0:08:40.50,0:08:43.10,Default,,0000,0000,0000,,seems to think that gene drives\Nwere not actually
Dialogue: 0,0:08:43.10,0:08:44.58,Default,,0000,0000,0000,,that frightening or dangerous.
Dialogue: 0,0:08:44.58,0:08:47.07,Default,,0000,0000,0000,,Partly because they believe that\Nscientists will be
Dialogue: 0,0:08:47.07,0:08:49.44,Default,,0000,0000,0000,,very cautious and responsible\Nabout using them.
Dialogue: 0,0:08:49.44,0:08:50.32,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:08:50.32,0:08:52.52,Default,,0000,0000,0000,,So far, that's been true.
Dialogue: 0,0:08:52.52,0:08:55.38,Default,,0000,0000,0000,,But gene drives also have\Nsome actual limitations.
Dialogue: 0,0:08:55.38,0:08:58.40,Default,,0000,0000,0000,,For one thing, they work in only\Nsexually reproducing species.
Dialogue: 0,0:08:58.40,0:09:01.88,Default,,0000,0000,0000,,So thank goodness, they can't be used\Nto engineer viruses or bacteria.
Dialogue: 0,0:09:01.88,0:09:05.24,Default,,0000,0000,0000,,Also, the trait spreads only with each\Nsuccesive genertion.
Dialogue: 0,0:09:05.24,0:09:08.73,Default,,0000,0000,0000,,So changing or eliminating a population\Nis practical only if that species
Dialogue: 0,0:09:08.73,0:09:11.10,Default,,0000,0000,0000,,has a fast reproductive cycle,\N
Dialogue: 0,0:09:11.10,0:09:14.19,Default,,0000,0000,0000,,like insects or maybe small vertebrates\Nlike mice or fish.
Dialogue: 0,0:09:14.19,0:09:16.53,Default,,0000,0000,0000,,In elephants or people, it would\Ntake centuries
Dialogue: 0,0:09:16.53,0:09:20.34,Default,,0000,0000,0000,,for a trait to spread widely enough\Nto matter.
Dialogue: 0,0:09:20.34,0:09:25.49,Default,,0000,0000,0000,,Also, even with CRISPR, it's not that easy\Nto engineer a truly devastating trait.
Dialogue: 0,0:09:25.49,0:09:27.68,Default,,0000,0000,0000,,Say you wanted to make a fruit fly\N
Dialogue: 0,0:09:27.68,0:09:30.30,Default,,0000,0000,0000,,that feeds on ordinary fruit instead\Nof rotting fruit
Dialogue: 0,0:09:30.30,0:09:33.07,Default,,0000,0000,0000,,with the aim of sabotaging \NAmerican agriculture.
Dialogue: 0,0:09:33.07,0:09:35.48,Default,,0000,0000,0000,,First you'd have to figure out\Nwhich genes control
Dialogue: 0,0:09:35.48,0:09:37.59,Default,,0000,0000,0000,,what the fly wants to eat,
Dialogue: 0,0:09:37.59,0:09:40.64,Default,,0000,0000,0000,,which is already a very long \Nand complicated project.
Dialogue: 0,0:09:40.64,0:09:43.82,Default,,0000,0000,0000,,Then you'd have to alter those genes\Nto change the fly's behavior
Dialogue: 0,0:09:43.82,0:09:45.44,Default,,0000,0000,0000,,to whatever you'd want it to be,
Dialogue: 0,0:09:45.44,0:09:48.09,Default,,0000,0000,0000,,which is an even longer \Nand more complicated project.
Dialogue: 0,0:09:48.09,0:09:49.81,Default,,0000,0000,0000,,And it might not even work because\N
Dialogue: 0,0:09:49.81,0:09:52.02,Default,,0000,0000,0000,,the genes that control\Nbehavior are complex.
Dialogue: 0,0:09:52.02,0:09:54.59,Default,,0000,0000,0000,,So if you're a terrorist and have \Nto choose between
Dialogue: 0,0:09:54.59,0:09:56.22,Default,,0000,0000,0000,,starting a grueling basic research program
Dialogue: 0,0:09:56.22,0:09:57.73,Default,,0000,0000,0000,,that will require years \Nof meticulous lab work
Dialogue: 0,0:09:57.73,0:09:59.40,Default,,0000,0000,0000,,and still might not pan out,
Dialogue: 0,0:09:59.40,0:10:00.77,Default,,0000,0000,0000,,or just blowing stuff up?
Dialogue: 0,0:10:00.77,0:10:03.24,Default,,0000,0000,0000,,You'll probably choose the later.
Dialogue: 0,0:10:03.24,0:10:05.62,Default,,0000,0000,0000,,This is especially true because\Nat least in theory,
Dialogue: 0,0:10:05.62,0:10:09.01,Default,,0000,0000,0000,,it should be pretty easy to build\Nwhat's called a reversal drive.
Dialogue: 0,0:10:09.01,0:10:13.03,Default,,0000,0000,0000,,That's one that basically overwrites\Nthe change made by the first gene drive.
Dialogue: 0,0:10:13.03,0:10:15.30,Default,,0000,0000,0000,,So if you don't like the effects \Nof a change,
Dialogue: 0,0:10:15.30,0:10:18.16,Default,,0000,0000,0000,,you can just release a second drive\Nthat will cancel it out,
Dialogue: 0,0:10:18.16,0:10:21.57,Default,,0000,0000,0000,,at least in theory.
Dialogue: 0,0:10:21.57,0:10:24.85,Default,,0000,0000,0000,,Okay, so where does this leave us?
Dialogue: 0,0:10:24.85,0:10:29.35,Default,,0000,0000,0000,,We now have the ability to change\Nentire species at will.
Dialogue: 0,0:10:29.35,0:10:30.81,Default,,0000,0000,0000,,Should we?
Dialogue: 0,0:10:30.81,0:10:34.25,Default,,0000,0000,0000,,Are we gods now?
Dialogue: 0,0:10:34.25,0:10:36.32,Default,,0000,0000,0000,,I'm not sure I'd say that.
Dialogue: 0,0:10:36.32,0:10:38.66,Default,,0000,0000,0000,,But I would say this:
Dialogue: 0,0:10:38.66,0:10:41.43,Default,,0000,0000,0000,,First, some very smart people\Nare even now debating
Dialogue: 0,0:10:41.43,0:10:43.84,Default,,0000,0000,0000,,how to regulate gene drives.
Dialogue: 0,0:10:43.84,0:10:46.42,Default,,0000,0000,0000,,At the same time, some other\Nvery smart people
Dialogue: 0,0:10:46.42,0:10:48.60,Default,,0000,0000,0000,,are working hard to create\Nsafeguards,
Dialogue: 0,0:10:48.60,0:10:52.18,Default,,0000,0000,0000,,like gene drives that self regulate\Nor petter out after a few generations.
Dialogue: 0,0:10:52.18,0:10:53.43,Default,,0000,0000,0000,,That's great.
Dialogue: 0,0:10:53.43,0:10:56.47,Default,,0000,0000,0000,,But this technology still requires\Na conversation.
Dialogue: 0,0:10:56.47,0:10:59.72,Default,,0000,0000,0000,,And given the nature of gene drives,
Dialogue: 0,0:10:59.72,0:11:02.37,Default,,0000,0000,0000,,that conversation has to be global.
Dialogue: 0,0:11:02.37,0:11:05.53,Default,,0000,0000,0000,,What if Kenya wants to use a drive\Nthat Tanzania doesn't?
Dialogue: 0,0:11:05.53,0:11:09.56,Default,,0000,0000,0000,,Who decides whether to release\Na gene drive that can fly?
Dialogue: 0,0:11:11.29,0:11:13.84,Default,,0000,0000,0000,,I don't have the answer to that question.
Dialogue: 0,0:11:13.84,0:11:15.88,Default,,0000,0000,0000,,All we can do going forward, I think,
Dialogue: 0,0:11:15.88,0:11:18.67,Default,,0000,0000,0000,,is talk honestly about \Nthe risks and benefits
Dialogue: 0,0:11:18.67,0:11:21.94,Default,,0000,0000,0000,,and take responsibility for our choices.
Dialogue: 0,0:11:21.94,0:11:25.96,Default,,0000,0000,0000,,By that I mean, not just the choice\Nto use a gene drive,
Dialogue: 0,0:11:25.96,0:11:29.42,Default,,0000,0000,0000,,but also the choice not to use one.
Dialogue: 0,0:11:29.42,0:11:32.35,Default,,0000,0000,0000,,Humans have a tendency to assume\Nthat the safest option
Dialogue: 0,0:11:32.35,0:11:35.06,Default,,0000,0000,0000,,is to preserve the status quo.
Dialogue: 0,0:11:35.06,0:11:37.71,Default,,0000,0000,0000,,But that's not always the case.
Dialogue: 0,0:11:37.71,0:11:41.36,Default,,0000,0000,0000,,Gene drives have risks and those\Nneed to be discussed,
Dialogue: 0,0:11:41.36,0:11:45.21,Default,,0000,0000,0000,,but malaria exists now and kills\N1,000 people a day.
Dialogue: 0,0:11:45.21,0:11:48.86,Default,,0000,0000,0000,,To combat it, we spray pesticides\Nthat do grave damage to other species,
Dialogue: 0,0:11:48.86,0:11:51.60,Default,,0000,0000,0000,,including amphibians and birds.
Dialogue: 0,0:11:51.60,0:11:54.34,Default,,0000,0000,0000,,So when you hear about gene drives\Nin the coming months,
Dialogue: 0,0:11:54.34,0:11:57.19,Default,,0000,0000,0000,,and trust me, you will be \Nhearing about them,
Dialogue: 0,0:11:57.19,0:11:58.63,Default,,0000,0000,0000,,remember that.
Dialogue: 0,0:11:58.63,0:12:00.68,Default,,0000,0000,0000,,It can be frightening to act,
Dialogue: 0,0:12:00.68,0:12:04.92,Default,,0000,0000,0000,,but sometimes, not acting\Nis worse.
Dialogue: 0,0:12:04.92,0:12:07.95,Default,,0000,0000,0000,,(Applause)