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magine you were alive back in the 1980's,
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and were told that computers would soon take over everything:
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from shopping, to dating, and the stock market,
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that billions of people would be connected via a kind of web,
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that you would own a handheld device, orders of magnitudes more powerful than supercomputers.
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It would seem absurd, but then, all of it happened.
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Science fiction became our reality, and we don't even think about it.
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We're at a similar point today with genetic engineering.
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So, let's talk about it.
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Where it came from, what we're doing right now,
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and about a recent breakthrough, that will change how we live and what we perceive as normal, forever.
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Humans have been engineering life for thousands of years.
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Through selective breeding, we strengthened useful traits in plants and animals.
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We became very good at this, but never fully understood how it worked.
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Until we discovered the code of life, Deoxyribonucleic Acid—DNA.
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A complex molecule that guides the growth, development, function, and reproduction of everything alive.
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Information is encoded in the structure of the molecule.
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Four nucleotides are paired and make up a code that carries instructions.
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Change the instructions and you change the being carrying it.
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As soon as DNA was discovered, people tried to tinker with it.
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In the 1960's, scientist bombarded plants with radiation to cause random mutations in the genetic code.
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The idea was to get a useful plant variation by pure chance.
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Sometimes it actually worked too.
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In the 70's, scientists inserted DNA
snippets into bacteria, plants, and animals
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to study and modify them for
research, medicine, agriculture, and for fun.
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The earliest genetically modified animal
was born in 1974, making mice a standard tool for research, saving millions of lives.
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In the 80's, we got commercial. The first patent was given for a microbe engineered to absorb oil.
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Today we produce many chemicals by means of engineered life,
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like life-saving clotting factors, growth hormones, and insulin.
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All things we had to harvest from the organs of animals before that.
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The first food modified in the lab went on sale in 1994: the Flavr Savr tomato,
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a tomato given a much longer shelf life where an extra gene that suppresses the build-up of a rotting enzyme.
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But GM food and the controversy surrounding them deserve a video of their own.
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In the 1990's, there was also a brief
foray into human engineering.
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To treat maternal infertility, babies were made that carried genetic information from 3 humans.
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Making them the first humans ever to have 3 genetic parents.
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Today there are super muscled pigs, fast-growing salmon, featherless chicken, and see-through frogs.
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On the fun side, we made things glow in the dark.
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Fluorescent zebrafish are available for
as little as ten dollars.
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All of this is already very impressive, but until recently
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gene editing was extremely expensive,
complicated, and took a long time to do.
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This has now changed with a revolutionary new technology now entering the stage—CRISPR.
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Overnight, the costs of engineering have shrunk by 99 %.
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Instead of a year, it takes a few weeks to conduct experiments, and basically everybody with a lab can do it.
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It's hard to get across how big a technical revolution CRISPR is.
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It literally has the potential to change humanity forever.
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Why did this sudden revolution happen and how does it work?
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Bacteria and viruses have been fighting
since the dawn of life.
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So-called bacteriophages or phages hunt bacteria.
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In the ocean, phages kill 40 % of them every single day.
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Phages do this by inserting their own genetic code into the bacteria and taking them over to use them as factories.
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The bacteria tried to resist but failed most the time because their protection tools are too weak,
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But sometimes bacteria survive an attack.
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Only if they do so can they activate their most effective antivirus system:
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they save a part of the virus DNA in their own genetic code in a DNA archive called CRISPR.
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Here it's stored safely until it's needed.
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When the virus attacks again, the bacterium quickly makes an RNA copy from the DNA archive and arms a secret weapon—a protein called CAS9.
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The protein now scans the bacterium's
insides for signs of the virus invader
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by comparing every bit of DNA it finds to the sample from the archive.
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When it finds a 100-percent perfect match,
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it's activated and cuts out the virus
DNA, making it useless, protecting the bacterium against the attack.
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What's special is that CAS9 is very
precise, almost like a DNA surgeon.
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The revolution began when scientists figured out that the CRISPR system is programmable.
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You can just give it a copy of DNA you want to modify and put the system into a living cell.
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If the old techniques of genetic manipulation were like a map, CRISPR is like a GPS system.
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Aside from being precise, cheap, and easy, CRISPR offers the ability to edit live cells,
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to switch genes on and off, and target and study particular DNA sequences.
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It also works for every type of cell: microorganisms, plants, animals, or humans.
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But despite the revolution CRISPR is for science, it's still just a first generation tool.
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More precise tools are already being created and used as we speak.
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In 2015, scientists use CRISPR to cut the HIV virus out of living cells
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from patients in the lab, proving that it was possible.
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Only about a year later, they carried out a larger scale project with rats
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that had the HIV virus in basically all of their body cells.
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By simply injecting CRISPR into the rats tails,
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they were able to remove more than 50 %
of the virus from cells all over the body.
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In a few decades, a CRISPR therapy
might cure HIV and other retroviruses,
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viruses that hide inside human DNA like
Herpes could be eradicated this way.
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CRISPR could also defeat one of our worst enemies—cancer.
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Cancer occurs when cells refuse to die and keep multiplying while concealing themselves from the immune system.
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CRISPR gives us the means to edit your immune cells and make them better cancer hunters.
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Getting rid of cancer might eventually mean
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getting just a couple of injections of a
few thousand of your own cells
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that have been engineered in the lab to heal you for good.
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The first clinical trial for a CRISPR cancer treatment on human patients was approved in early 2016 in the
US.
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Not even a month later, Chinese scientists announced that they would treat lung cancer patients
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with immune cells modified with CRISPR in August 2016.
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Things are picking up pace quickly.
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And then there are genetic diseases.
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There are thousands of them and they range from mildly annoying to deadly or entail decades of suffering.
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With a powerful tool like CRISPR, we may be able to end this.
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Over 3,000 genetic diseases are caused by a single incorrect letter in your DNA.
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We are already building a modified
version of CAS9 that is made to change just a single letter, fixing the disease in the cell.
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In a decade or two, we could possibly cure thousands of diseases forever.
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But all of these medical applications have one thing in common:
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they are limited to the individual and die with them,
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except if you use them on reproductive cells or very early embryos.
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But CRISPR can and probably will be used for much more:
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the creation of modified humans—designer babies—and will mean gradual,
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but irreversible changes to the human gene pool.
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The means to edit the genome of a human embryo already exists.
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Though the technology is still in its early stages, but it has already been attempted twice.
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In 2015 and 2016, Chinese scientists experimented with human embryos and were partially successful on their second attempt.
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They showed the enormous challenges we still face in gene editing embryos,
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but also that scientists are
working on solving them.
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This is like the computer in the 70's. There will be better computers.
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Regardless of your personal take on
genetic engineering, it will affect you.
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Modified humans could alter the genome of our entire species, because their engineered traits will be passed on to their children
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and could spread over generations, slowly modifying the whole gene pool of humanity.
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It will start slowly. The first designer babies will not be overly designed.
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It's most likely that they will be created to eliminate a deadly genetic disease running in a family.
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As the technology progresses and gets
more refined, more and more people may argue that not using genetic modification is unethical,
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because it condemns children to preventable suffering and death and denies them the cure.
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But as soon as the first engineered kid is born, a door is opened that can't be closed anymore.
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Early on, vanity traits will mostly be left alone.
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But as genetic modification becomes more accepted and our knowledge of our genetic code enhances, the temptation will grow.
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If you make your offspring immune to Alzheimer, why not also give them an enhanced metabolism?
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Why not throw in perfect eyesight?
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How about height or muscular structure?
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Full hair?
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How about giving your child the gift of
extraordinary intelligence?
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Huge changes are made as a result of the personal decisions of millions of individuals that accumulate.
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This is a slippery slope. Modified humans could become the new standard.
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But as engineering becomes more
normal and our knowledge improves,
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we could solve the single biggest mortality risk factor: aging.
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Two-thirds of the 150,000 people who died today will die of age-related causes.
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Currently we think aging is caused by the accumulation of damage to our cells,
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like DNA breaks and the systems responsible for fixing those wearing off over time.
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But there are also genes that directly affect aging.
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A combination of genetic engineering and other therapy could stop or slow down aging, maybe even reverse it.
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We know from nature that there are animals immune to aging.
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Maybe we could even borrow a few genes for ourselves.
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Some scientists even think biological aging could be something that eventually just stops being a thing.
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We would still die at some point, but instead of doing so in hospitals at age 90,
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we might be able to spend a few thousand years with our loved ones.
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Research into this is in its infancy,
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and many scientists are rightly skeptical about the end of aging.
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The challenges are enormous and maybe it is unachievable,
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but it is conceivable the people alive today might be the first to profit from effective anti aging therapy.
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All we might need is for someone to convince a smart billionaire to make it their next problem to solve.
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On a bigger scale, we certainly could solve many problems by having a modified population.
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Engineered humans might be better equipped to cope with high-energy food,
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eliminating many diseases of civilization like obesity.
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In possession of a modified immune system, with a library of potential threats,
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we might become immune to most diseases that haunt us today.
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Even further into the future, we could engineer humans to be equipped for extended space travel
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and to cope with different conditions on another planets,
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which would be extremely helpful in
keeping us alive in our hostile universe.
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Still, a few major challenges await us: some technological, some ethical.
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Many of you watching will feel uncomfortable and fear that we will create a world in which we will reject non-perfect humans
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and pre-select features and qualities based on our idea of what's healthy.
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The thing is we are already living in
this world.
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Tests for dozens of genetic diseases or complications have become standard for pregnant women in much of the world.
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Often the mere suspicion of a genetic defect can lead to the end of a pregnancy.
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Take Down syndrome for example, one of the most common genetic defects.
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In Europe, about 92 % of all pregnancies where it's detected are terminated.
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The decision to terminate pregnancy is incredibly personal,
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but it's important to acknowledge the reality that we are pre-selecting humans based on medical conditions.
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There is also no use in pretending this will change,
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so we have to act carefully and respectfully as we advance the technology and can make more and more
selections.
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But none of this will happen soon.
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As powerful as CRISPR is—and it is, it's not infallible yet.
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Wrong edits still happen as well as unknown errors that can occur anywhere in the DNA and might go unnoticed.
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The gene edit might achieve the desired result—disabling a disease,
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but also might accidentally trigger unwanted changes.
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We just don't know enough yet about the
complex interplay of our genes to avoid unpredictable consequences.
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Working on accuracy and monitoring methods is a major concern as the first human trials begin.
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And since we've discussed a possible positive future, there are darker visions too.
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Imagine what a state like North Korea
could do if they embraced genetic engineering.
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Could a state cement its rule forever by forcing gene editing on their subjects?
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What would stop a totalitarian regime from engineering an army of modified super soldiers?
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It is doable in theory.
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Scenarios like this one are far, far off into the future, if they ever become possible at all.
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But the basic proof of concept for genetic engineering like this already exists today.
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The technology really is that powerful.
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While this might be a tempting reason to ban genetic editing and related research, that would certainly be a mistake.
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Banning human genetic engineering would only lead to the science wandering off
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to a place with jurisdiction and rules
that we are uncomfortable with.
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Only by participating can we make sure that further research is guided by caution, reason, oversight, and transparency.
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Do you feel uncomfortable now?
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Most of us have something wrong with them.
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In the future that lies ahead of us, would we have been allowed to exist?
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The technology is certainly a bit scary, but we have a lot to gain,
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and genetic engineering might just be a step in the natural evolution of intelligent species in the universe.
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We might end disease.
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We could extend our life expectancy by centuries and travel to the stars.
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There's no need to think small when it comes to this topic.
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Whatever your opinion on genetic engineering, the future is approaching no matter what.
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What has been insane science fiction is about to become our new reality,
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a reality full of opportunities and challenges.
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If you want to support to explaining complicated stuff and maybe get your own bird in return, you can do so here.
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If you want to learn more about CRISPR, we put the sources and further reading in the description.
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More videos about the whole topic area will follow.
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