Gene editing can now change an entire species — forever | Jennifer Kahn

Gene editing can now change an entire species — forever | Jennifer Kahn


So this is a talk about gene drives, but I’m going to start
by telling you a brief story. 20 years ago, a biologist
named Anthony James got obsessed with the idea
of making mosquitos that didn’t transmit malaria. It was a great idea,
and pretty much a complete failure. For one thing, it turned out
to be really hard to make a malaria-resistant mosquito. James managed it, finally,
just a few years ago, by adding some genes
that make it impossible for the malaria parasite
to survive inside the mosquito. But that just created another problem. Now that you’ve got
a malaria-resistant mosquito, how do you get it to replace
all the malaria-carrying mosquitos? There are a couple options, but plan A was basically to breed up a bunch of the new
genetically-engineered mosquitos release them into the wild and hope that they pass on their genes. The problem was that you’d have to release literally 10 times the number
of native mosquitos to work. So in a village with 10,000 mosquitos, you release an extra 100,000. As you might guess, this was not a very popular strategy
with the villagers. (Laughter) Then, last January,
Anthony James got an email from a biologist named Ethan Bier. Bier said that he
and his grad student Valentino Gantz had stumbled on a tool
that could not only guarantee that a particular genetic trait
would be inherited, but that it would spread
incredibly quickly. If they were right,
it would basically solve the problem that he and James had been
working on for 20 years. As a test, they engineered two mosquitos
to carry the anti-malaria gene and also this new tool, a gene drive, which I’ll explain in a minute. Finally, they set it up
so that any mosquitos that had inherited the anti-malaria gene wouldn’t have the usual white eyes,
but would instead have red eyes. That was pretty much just for convenience so they could tell just at a glance
which was which. So they took their two
anti-malarial, red-eyed mosquitos and put them in a box
with 30 ordinary white-eyed ones, and let them breed. In two generations, those had produced
3,800 grandchildren. That is not the surprising part. This is the surprising part: given that you started
with just two red-eyed mosquitos and 30 white-eyed ones, you expect mostly white-eyed descendants. Instead, when James opened the box, all 3,800 mosquitos had red eyes. When I asked Ethan Bier about this moment, he became so excited that he was literally
shouting into the phone. That’s because getting
only red-eyed mosquitos violates a rule that is the absolute
cornerstone of biology, Mendelian genetics. I’ll keep this quick, but Mendelian genetics
says when a male and a female mate, their baby inherits half
of its DNA from each parent. So if our original mosquito was aa
and our new mosquito is aB, where B is the anti-malarial gene, the babies should come out
in four permutations: aa, aB, aa, Ba. Instead, with the new gene drive, they all came out aB. Biologically, that shouldn’t
even be possible. So what happened? The first thing that happened was the arrival of a gene-editing tool
known as CRISPR in 2012. Many of you have probably
heard about CRISPR, so I’ll just say briefly that CRISPR
is a tool that allows researchers to edit genes very precisely,
easily and quickly. It does this by harnessing a mechanism
that already existed in bacteria. Basically, there’s a protein
that acts like a scissors and cuts the DNA, and there’s an RNA molecule
that directs the scissors to any point on the genome you want. The result is basically
a word processor for genes. You can take an entire gene
out, put one in, or even edit just a single
letter within a gene. And you can do it in nearly any species. OK, remember how I said that gene drives
originally had two problems? The first was that it was hard
to engineer a mosquito to be malaria-resistant. That’s basically gone now,
thanks to CRISPR. But the other problem was logistical. How do you get your trait to spread? This is where it gets clever. A couple years ago, a biologist
at Harvard named Kevin Esvelt wondered what would happen if you made it so that
CRISPR inserted not only your new gene but also the machinery
that does the cutting and pasting. In other words, what if CRISPR
also copied and pasted itself. You’d end up with a perpetual
motion machine for gene editing. And that’s exactly what happened. This CRISPR gene drive that Esvelt created not only guarantees
that a trait will get passed on, but if it’s used in the germline cells, it will automatically copy and paste
your new gene into both chromosomes
of every single individual. It’s like a global search and replace, or in science terms, it makes
a heterozygous trait homozygous. So, what does this mean? For one thing, it means we have
a very powerful, but also somewhat alarming new tool. Up until now, the fact that gene drives
didn’t work very well was actually kind of a relief. Normally when we mess around
with an organism’s genes, we make that thing
less evolutionarily fit. So biologists can make
all the mutant fruit flies they want without worrying about it. If some escape, natural selection
just takes care of them. What’s remarkable and powerful
and frightening about gene drives is that that will no longer be true. Assuming that your trait does not have
a big evolutionary handicap, like a mosquito that can’t fly, the CRISPR-based gene drive
will spread the change relentlessly until it is in every single individual
in the population. Now, it isn’t easy to make
a gene drive that works that well, but James and Esvelt think that we can. The good news is that this opens
the door to some remarkable things. If you put an anti-malarial gene drive in just 1 percent of Anopheles mosquitoes, the species that transmits malaria, researchers estimate that it would spread
to the entire population in a year. So in a year, you could virtually
eliminate malaria. In practice, we’re still a few years out
from being able to do that, but still, a 1,000 children
a day die of malaria. In a year, that number
could be almost zero. The same goes for dengue fever,
chikungunya, yellow fever. And it gets better. Say you want to get rid
of an invasive species, like get Asian carp
out of the Great Lakes. All you have to do is release a gene drive that makes the fish produce
only male offspring. In a few generations,
there’ll be no females left, no more carp. In theory, this means we could restore
hundreds of native species that have been pushed to the brink. OK, that’s the good news, this is the bad news. Gene drives are so effective that even an accidental release
could change an entire species, and often very quickly. Anthony James took good precautions. He bred his mosquitos
in a bio-containment lab and he also used a species
that’s not native to the US so that even if some did escape, they’d just die off, there’d be nothing
for them to mate with. But it’s also true that if a dozen
Asian carp with the all-male gene drive accidentally got carried
from the Great Lakes back to Asia, they could potentially wipe out
the native Asian carp population. And that’s not so unlikely,
given how connected our world is. In fact, it’s why we have
an invasive species problem. And that’s fish. Things like mosquitos and fruit flies, there’s literally no way to contain them. They cross borders
and oceans all the time. OK, the other piece of bad news is that a gene drive
might not stay confined to what we call the target species. That’s because of gene flow, which is a fancy way of saying
that neighboring species sometimes interbreed. If that happens, it’s possible
a gene drive could cross over, like Asian carp could infect
some other kind of carp. That’s not so bad if your drive
just promotes a trait, like eye color. In fact, there’s a decent
chance that we’ll see a wave of very weird fruit flies
in the near future. But it could be a disaster if your drive is deigned
to eliminate the species entirely. The last worrisome thing
is that the technology to do this, to genetically engineer an organism
and include a gene drive, is something that basically any lab
in the world can do. An undergraduate can do it. A talented high schooler
with some equipment can do it. Now, I’m guessing
that this sounds terrifying. (Laughter) Interestingly though,
nearly every scientist I talk to seemed to think that gene drives were not
actually that frightening or dangerous. Partly because they believe
that scientists will be very cautious and responsible
about using them. (Laughter) So far, that’s been true. But gene drives also have
some actual limitations. So for one thing, they work
only in sexually reproducing species. So thank goodness, they can’t be used
to engineer viruses or bacteria. Also, the trait spreads
only with each successive generation. So changing or eliminating a population is practical only if that species
has a fast reproductive cycle, like insects or maybe
small vertebrates like mice or fish. In elephants or people,
it would take centuries for a trait to spread
widely enough to matter. Also, even with CRISPR, it’s not that easy
to engineer a truly devastating trait. Say you wanted to make a fruit fly that feeds on ordinary fruit
instead of rotting fruit, with the aim of sabotaging
American agriculture. First, you’d have to figure out which genes control
what the fly wants to eat, which is already a very long
and complicated project. Then you’d have to alter those genes
to change the fly’s behavior to whatever you’d want it to be, which is an even longer
and more complicated project. And it might not even work, because the genes
that control behavior are complex. So if you’re a terrorist
and have to choose between starting a grueling
basic research program that will require years of meticulous
lab work and still might not pan out, or just blowing stuff up? You’ll probably choose the later. This is especially true
because at least in theory, it should be pretty easy
to build what’s called a reversal drive. That’s one that basically overwrites
the change made by the first gene drive. So if you don’t like
the effects of a change, you can just release a second drive
that will cancel it out, at least in theory. OK, so where does this leave us? We now have the ability
to change entire species at will. Should we? Are we gods now? I’m not sure I’d say that. But I would say this: first, some very smart people are even now debating
how to regulate gene drives. At the same time,
some other very smart people are working hard to create safeguards, like gene drives that self-regulate
or peter out after a few generations. That’s great. But this technology still requires
a conversation. And given the nature of gene drives, that conversation has to be global. What if Kenya wants to use a drive
but Tanzania doesn’t? Who decides whether to release
a gene drive that can fly? I don’t have the answer to that question. All we can do going forward, I think, is talk honestly
about the risks and benefits and take responsibility for our choices. By that I mean, not just the choice
to use a gene drive, but also the choice not to use one. Humans have a tendency to assume
that the safest option is to preserve the status quo. But that’s not always the case. Gene drives have risks,
and those need to be discussed, but malaria exists now
and kills 1,000 people a day. To combat it, we spray pesticides
that do grave damage to other species, including amphibians and birds. So when you hear about gene drives
in the coming months, and trust me, you will
be hearing about them, remember that. It can be frightening to act, but sometimes, not acting is worse. (Applause)

100 Comments

  1. Has anyone thought for a second that natures' form of combating a virus (humans) is through mosquitoes? We have caused so much devastation to this world should we not try to balance nature, instead of fighting it? Genocide why not we are the better species. Hum… Anybody remembers the name of that guy in history? The one that wanted the blue-eyed people to be the supreme one?

  2. if human A have genetically modified blu eyes and human B have genetically modified green eyes, what will happen if they have a baby? Will the baby both blue and green eyes or the baby will never be born?

  3. Can we gene drive all Sketo‘s to spread another GeneDrive of my RNA to all breading humans there making all humans to spread my genetic inheritance through out the world with out anyone having to say “and ya didn’t take me to dinner first”. ?

  4. What happened with those animals which eat these modified spieces?And What hapnds whit us at the end of the food chain?Lets say a frog is adopted during millions of years to eat bugs and Moskitos.Now you alter ,modify that moskito,when the frog eat it,I guess it’s going to have an effect on the frog maybe?Maybe effect which is going to occur a few generations down the road.

  5. This presenter doesn’t come across correctly. The smirking smile doesn’t quite communicate the seriousness of the situation.

  6. Wake up — She basically just explained how they are going to mix Fallen Angel blood with humans by adding the gene drive drive, and letting humanity populate, so that the very next and additional populations have changed. They can then create a "pest" control to kill off all the mosquitos that don't have this drive, ie, humans who weren't changed. They are telling Christians what they plan to do!

  7. Wow. This new tech creates so many new questions and discussion points that need to be addressed publically before it gets used even once outside of the lab. Man vs. Nature, Morals and Ethics vs. Evolution, gene banks and gene safety. Technological means for the preservation of life vs. Revising the global economy to increase world health and eliminate poverty vs over population of areas. Do we leave to nature cul as it sees fit to preserve everything it's been in charge of for billions of years or do we risk accidentally biting off more than we can chew?

  8. 7:05

    "And if those days will not be pruned, not, as it were, would all-any flesh be saved; but because of the outchosen ones those the days will be pruned" (M24:22)

  9. This could be the end of mankind. The end of a race. It makes me think of Jurassic park Jeff Goldblum. Scientist got so caught up on asking if they could do something, they forgot to ask if they should! God help us all.

  10. This is amazing but how soon would the government use it for control population. & can we really be sure that bacteria and viruses won’t mutate as well once in the hosts body? Sounds like apocalypse isn’t too far. Sci-fi coming true.

  11. Funny how the PTB push this agenda, with the implication of saving lives, while the very rich are back pushing population reduction. Clearly the good of the people is not the objective.

  12. I wonder who decides what genes are considered defective ?. Not many know that a defective gene was responsible for half of Europe surviving the Black Death, a trait that was passed on to all eurooean settlers of North America.

    My guess is that scientists involved may have an incomplete and pollyanna picture of this proposal.

  13. Imagine malaria was cured a hundred years ago. Would we not by now have drowned in people? We have to ask ourselves, is nature doing us a favour, with killing us off?

  14. 🤣🤣😂🤣😂😂 better have a red eye skeeter bite a human first. I would imagine a mutation in the parasites to

  15. So, we may someday be able to correct non-white humans worldwide by engineering a bacteria to turn them into true Aryans… Interesting. I'll send a mail to Reichführer Himmler sofort !

  16. To what extent can genes be edited? Is it like engineering where progress is made gradually, like first making a car that goes 50 mph and gradually making faster and faster cars. Or will it be like, going from worm to elder god in a week? How fast is the evolution of gene editing?

  17. This is what Ridley Scott was trying to say when he directed the movie "Prometheus" and talking about "the engineers" and how they wanted to wipe out the human race they created.

  18. Listen to the people that work in this field 99.9% will tell you this was a huge mistake. This person isnt even a real scientist he still dosnt share hes ''reasearch'' with the scientific community. Im not working in this field but as I know the genome is still a big blackbox with an almost undefined number of possibilits how could anyone know exactly what hes doing?

  19. Somewhere I read that mosquitoes get a little sick from the malaria parasite. Resistance to malaria would make them more fit … to transmit diseases like Zika and Chikungunya and to pester or even bleed animals and people to death?

  20. scientists would be cautious and responsible about using Crispr and gene drives?
    https://www.theatlantic.com/science/archive/2018/12/15-worrying-things-about-crispr-babies-scandal/577234/

  21. The Phrase "playing GOD" must be better understood; Most people think it mean BEING powerful enough to change anything you want; however, I believe it really means "Being powerful enough to change anything with 100% confidence that one thousand years later it will not be a move that wipes out all life….everywhere" I believe that no one alive today can see the long term effects of having a mosquito that DOES NOT cary malaria. It may mean the end of life on earth! For example; Imagine the mosquitos pass the gene to Bees, now we may not know that bees have some connection with malaria that allows them to be effective in their lives…etc…Yada Yada Yada…no bees NO LIFE ON Earth. EVERYTHING in Nature is connected and we are just scratching the surface of that knowledge….over confidence is a scary thing! good luck Earth, good luck humans, we are about to kill ourselves in many ways. Destroying environment, artificial intelligence, GMOs, over specialization of everything! the list goes on Im sure…..Harold

  22. Puuuhhllleeeaaase!!! Get some BALANCE!! Watch the 'mother of CRISPr', Ellen Jorgenson, PhD Molecular Biology, get the OTHER side of the claimed 'accuracy' of CRISPr…… how deeply disappointing. From 6.20 it gets REAL interesting:
    https://www.youtube.com/watch?v=1BXYSGepx7Q&list=WL&index=43

  23. People shouldn't be scared or say stuff like "are we God's now". The truth is we forget that we too are evolving. Science is part of who we we are our evolution

  24. When she said "A high schooler with some equipment could do it" i was like… OMG IM GONNA DESTROY THE WORLD TOMMORROW MORNING :v

  25. I don't think humans are ready for this technology. Just because we can doesn't mean we should. If it is to be used, I think the only ethical purpose would be for reversing the effects of invasive species, not for wiping out species; we don't know what the unintended consequences are and we should proceed very cautiously.

  26. Maybe these lower IQ “scientist”, are too stupid to see what they are doing, funny how these idiots are always talking about “diversity”, but have created anti-“diversity” force mutation plague, but these smart people will make their mistakes just like Monsanto and everybody else will have to pay.

  27. How do you account for unintentional consequences like consumption of Asian carp in a raw status so as to absorb genes in close species or differing species causing blindness insteadof eye color changes because of non intended data sets?

  28. Me, an undergrad trying to get into a lab that uses CRISPR CAS and was looking up videos on the subject: I FEEL VERY ATTACKED RIGHT NOW, lol.

  29. Oh this is just great, because we humans are known for making great choices and there are definitely no intelligent psychopaths that exist……lmao.

  30. Cloned life forms gene manipulation pretty soon the fact of the matter is that people WILL become designer life and everyone will eventually look the same and anyone now can do this as the narrator said even a highschool student can accomplish this (THINK ABOUT THAT)and as Trump is head of the us was bad enough all it will take is another catastrophe to restart humanity like floods space debris and so on to We have near 60 ish dna letters and only utilize 25 ish we have been genetically stunted evolution man is becoming god and before the great flood we where more advanced then we believe

  31. This lady states "if your a terrorist with the learned knowledge to utilize this but would rather blow things up"! Are you serious lady

  32. There has been a rise in the amount of sociopaths being groomed by the conditions of modern society and undoubtedly would take on these feats to engineer a strange anomaly to be released into the wild. Why not? CRISPR can be utilized for reverse analysis to discover the regulatory mechanisms which govern everything, including animal behavior. Potentially.

  33. @ 10:35, she's saying that we can reverse certain characteristics of a modified class by releasing second modified class .

    As if super smart modified terrorists/bad guys let their superpower take away.

  34. This is awesome lecture!
    I hope this technology will advance to a practical level and be used in a good way.

  35. Why all the focus on Malaria? MMS isn't particularly useful for many illnesses, but it sure works on Malaria and it's a whole lot quicker and easier. Track record is there and proven. They should pick a better example.

  36. Thank you for taking the time to share with those that are all trusting of scientists, and media, because this is just ONE THING that you will not hear on tv. Ok, now they can put their blindfolds back on.

  37. We are only human and will make mistakes with this. Unthinkable changes to the world will happen, but might those changes eliminate disease. Imagine if they could do this to viruses?

  38. What really astonishes me the most isn't that CRISPR can be used by high school students to edit genes but that Scientists around the world are able to write biological TRAIT sequences into genes. That is essentially GOD mode just short of creating new life.

  39. 08:49 16/07/2019
    What do you think? I think in the near future we will start to see ads like this.
    Send us your DNA Code and we will send by return post a 5mtr spool of your DNA
    This will also come with a free tube of human DNA super glue, as a special offer.
    All you need to do is take a photo of your body part that fell off and feeds it into your cad program. this will generate a G-code slicing layout. Just place this in the slot of your
    3D printer and press go. after a little time of printing, you will now have a brand new nose, or ear, maybe a complete foot. be quick offer ends soon. Malc UK

  40. This is NOTHING new, used to happen in old times, this is where mythological creatures came from. Splicing DNA between animals, men and horse, centaurs, eagle and lion, gryhpons. Its lost knowledge, we were told this was not possible so we would never try. It creates monsters. Prepare for a new world where biohacking and gene splicing is goin to become an issue most likely in other countries first.

  41. ok so i see im late to say anything on the subject… but it just seems to me like gene drives are going to be spreading the plague/and all other pathogens today's "civilized" man carries.since they are handled and created by carriers of nasty stuff. who's to say it really is sterile.. they might not even be aware of their inherent desire to spread.. It's Rooted in our genomes!! so much for brilliant educated people! your the problem.. kill your diseases first .. like sorry to say but all Europe. should be the first to experience the Crispr Joys of living, or dieing.. since they are talking about releasing some that can spread to everyone.. for all we know this is a Weapon to eliminate an entire population then take their lands… again!

  42. Revelation 9:6, "And in those days shall men seek death, and shall not find it; and shall desire to die, and death shall flee from them."

  43. The CDC says that in 2016, 445,000 people died from malaria. Saving these lives is great, but then what. These poor areas will now have even MORE poor people struggling to find food and clean water from depleted and nearly non existent resources. An increase in the millions is another problem.

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