Hello! I'm Hank Green, and this is SciShow! So, we made a video about this once before,
but some of the studies we cited turned out to be bunk, and, in general, I think we played
our cards too close to our chest when it comes to how we really feel about genetic engineering
here at SciShow. So, why are GMOs bad? They're not. They just aren’t, not intrinsically, and
certainly not for your health. We’ve been eating them for decades with
no ill effects, which makes sense, because a genetically modified organism is simply
an organism, like any other organism, that produces hundreds of thousands of proteins,
but one or two of them are proteins that were chosen specifically by us humans. Genetic engineering is necessary for the continued
success of the human experiment here on planet Earth. Just like the advent of nitrogen fixing allowed
for more fertile fields that saved millions from starvation, the fruits of genetic engineering
(sometimes literally) will help us face the significant challenges of a world with more
and more people and a climate that is less and less stable. Of course, just like nitrogen fixing also
allowed Germany to build bigger bombs, genetic engineering is a tool that can be used for
good or for evil. So, yes, it must be studied and controlled
and understood. But that understanding has to start with,
like, us. Right now! [Intro] If you live in the United States, you almost
certainly eat genetically modified organisms, or GMOs; thus far, it’s just plants, though
pretty much every kind of meat on the market was likely fed with GM corn at some point. And it won’t be long before the animals
themselves are genetically modified. In 2012, the FDA reviewed a new kind of Atlantic
salmon, engineered to have higher levels of growth hormone, using the genes of Pacific
salmon and an eel-like fish called the ocean pout. They concluded that the engineered fish was
safe and opened up the discussion for public comment, but still haven’t announced a final
decision. GMOs are everywhere in the US, pretty much
literally. 95% of sugar beets, 88% of corn, 94% of soybeans
grown in the U.S. contain traits -- like being insect-resistant or herbicide-resistant -- that
were engineered into them. And some crops are genetically modified simply
for human benefit. Around 500,000 children go blind every year
because of vitamin A deficiency. So a strain of rice has been developed that,
unlike normal rice, contains enough vitamin A to keep children healthy. Or, healthier, anyway. Now the term “genetically modified organism”
is actually somewhat of a misnomer. I mean, people have been genetically modifying
organisms since the invention of agriculture. Every plant and animal species has natural
genetic variability, and for thousands of years, we’ve harnessed this variability
by practicing artificial selection. We cultivate and breed organisms to emphasize
their most desirable traits - cows that produce more milk and squash plants that survive drought. Brassica oleracea, also known as wild cabbage,
has been bred so intensively that it is the wild ancestor of half a dozen different garden
staples, including broccoli, cabbage, cauliflower, brussel sprouts. kohlrabi and kale. Corn originally looked like this. Over the years of selective breeding, we have
turned it into a massive, crazy giant mutant version that we happily throw on the grill
without thinking of the centuries of breeding necessary to turn a grass seed into a sweet
and starchy masterpiece. But when we talk about GMOs today, we’re
actually talking about genetically engineered organisms or transgenic organisms. We’re talking about genes from one species
being extracted and then fused into the genome of a different species. This is called transgenesis, and though not
all GMO food is created this way, transgenic crops are by far the most common kind of genetically
engineered organisms you come across. But here's the thing: engineered organisms
aren’t anything new either -- we’ve been tinkering with food in laboratories for nearly
a hundred years. In the 1920s, scientists realized that they
could cause mutations in plants -- thereby creating more genetic diversity and possibly
more desirable traits-- by exposing them to x-rays, gamma rays, and various chemicals. Through the 1970s, these methods of mutation
breeding were quite popular, and completely unregulated and largely ignored by the public. Thousands of cultivars produced this way are
currently on the market. It's a kind of brute-force hack, just mess
the genes up, plant the seeds, and see what happens and then breed the cool new traits
back into various strains of crop. Then in 1983, scientists pioneered a new tactic,
where they successfully took a gene from an antibiotic-resistant bacterium and spliced
it into the DNA of a tobacco plant. Now, of course, antibiotic-resistant tobacco
doesn't have any real purpose, but it did prove that single-gene transfer was possible. The new practice of transgenics was born. Now the GM industry wasn’t really able to
take hold until 1994, when the USDA approved something called the Flavr Savr Tomato, a
fruit, invented by a California biotech company, that was altered so that it took longer to
ripen, giving it a longer shelf life. It was the first genetically engineered crop
sold to consumers. The Flavr Savr, though, didn’t last very
long -- partly because people didn’t like the taste, and partly because others, mainly
in Europe, were suspicious of its genetic alterations. The flavr savr, and its non-ideal flavr touched
off a debate that continues to rage. Today, most GMOs aren’t found in your produce
section like the Flavr Savr was. Instead, more than 90 percent of commercially
grown GM foods are commodity crops, staples like feed corn and soybeans, which have been
modified to resist herbicides or insects. These crops are used to make the ingredients
in lots of the processed foods we eat, or are used as fodder for animals that we later
enjoy consuming the flesh of. Probably the most well-known of these transgenic
crops are the so-called Roundup-ready crops -- foods like soybeans, corn, sugar beets,
cotton, alfalfa and canola that are engineered to resist the herbicide Roundup. These crops provide us with some, you might
say, digestible examples of how transgenic foods are engineered, why they’re made the
way they are, what they do as well as what they don't do. Let’s start with why they were made in the
first place. The active ingredient in the herbicide Roundup
is glyphosate, a chemical that inhibits an enzyme plants use to synthesize amino acids. By blocking this enzyme, Roundup stops plants
from making what they need to grow and metabolize food, thereby killing them. And it pretty much takes no prisoners. So much so that it can be hard to use around
plants that you don’t want to kill, like your crops. So in the early 1990s, the company that makes
Roundup, Monsanto, decided to develop crops that were resistant to glyphosate, so farmers
could spray the herbicide over their whole crop, but only kill the weeds. See, there are microorganisms that produce
an enzyme that is unaffected by glyphosate. All Monsanto had to do was transfer those
bacteria genes to food plants, and farmers could use Roundup to protect their crops without
killing them. So they extracted small pieces of bacterial
DNA that were responsible for making the enzyme and set about introducing them into plants. But how do you get the genes of a bacterium
into the nucleus of a plant cell? On the Tree of Life, plants and bacteria aren’t
even on the same branch! Well, it turns out there are a couple of pretty
interesting ways. The first involves gene guns. Yeah, you heard me! Gene guns! Gene guns do pretty much what they sound like
-- literally and kind of haphazardly, blasting DNA into plant cells. Most commonly used to engineer corn and rice
species, they start with tiny particles of gold that are coated with hundreds of copies
of a desired donor gene, called a transgene. Cells from the plant that’s gonna receive
the new genes are put into a vacuum chamber and then, fire away! The gene-covered gold particles are shot at
the cells using high-pressure gas. Once inside the nucleus of a plant cell, the
gold dissolves, and the scientists cross their fingers and hope that the DNA is taken up
by the chromosomes in the nucleus, which it sometimes it. Once the transgenes have been incorporated
into the plant’s DNA, it can then be bred into offspring plants. Not exactly elegant, but it's a heck of a
lot more subtle than just bombarding the seed with radiation and hoping for the best. Another more recent, and more effective, way
to create transgenic organisms involves using a soil-dwelling bacterium called Agrobacterium. This is a plant parasite and a natural genetic
engineer – it has an extra, and quite special, piece of DNA called a plasmid that can move
outside the bacterium and implant itself into a plant cell. In nature, the Agrobacterium uses this lil'
trick to re-code plant cells to grow food for it. But in the lab, engineers can use the plasmid
as a kind of carrier for fancy transgenes, using it to infuse plant cells with new genetic
material. So -- whether you’ve used the Agrobacterium
or the gene guns, you now have a new engineered crop plant. But you can’t just put that thing into the
ground -- you have to introduce this new genetic material into existing, traditional strains
of the crop. This last step, called backcross breeding,
involves repeatedly crossing the new transgenic plant with breeding stock, over and over again,
until you wind up with a new transgenic crop. At the end of the process, Monsanto had a
patented plant that could be sprayed with glyphosate and survive. Previously, plants would have to be seeded
far enough apart that machines could till away competing weeds, increasing soil loss
and costs to the farmer, not to mention fuel consumption. Plus, Monsanto gets a whole new, massive customer
base for glyphosate. It’s a long process – the whole thing
can take as long as 15 years – but that’s how just about all genetic engineering is
done to your food, whether scientists are putting a bacterium’s antibiotic resistance
into a tobacco plant, or an eel’s growth pattern into a salmon. Of course, then there’s the process of getting
the crop or animal approved for use, which can also take quite a number of years. At the moment, it’s extremely expensive,
though there are some technologies on the horizon that might make it cheaper. The fact that it’s so expensive and yet
still economically worth doing indicates how extremely useful GM crops can be. It also means that the companies that produce
them closely guard and restrict the patents and sale and growth and even research done
on the crops. One of the reasons engineered foods are attacked
so viciously is not because of the scientific consequences of their existence, but the economic
and cultural consequences of placing so much power over our food supply into the hands
of very few very large companies. The GMO debate has become something of a surrogate
for a much larger debate about economics that, frankly, is out of our league. There are scientific concerns about genetically
modified food. How does inserting a single gene, for example,
rather than swapping out huge hunks of genetic material, affect the genome at large? We used to think “not at all,” but it
turns out, the genome is more complicated than that. Additionally, many farmers save non-patented
seed for next year's crop, something you can't do with patented GM crop seed. But if your public domain seed was unintentionally
fertilized by a patented strain, you might find that suddenly the seed you saved from
last year's harvest to plant next year has genes owned by someone else. Someone who is, it turns out, suing you. And if your livelihood depends on selling
certified organic crops or selling into markets where GMOs are prohibited, the consequences
can be even more dire. And, of course, the traits we're engineering
into crops might have potential ecological effects, like if we're engineering in insect
resistance, we want to make sure that we're not harming the insects we DO like, like bees
and butterflies. But after having been consumed in hundreds
of millions of meals by me and probably by you, and having been studied for decades,
there has been zero implication that genetically modified food poses a danger to human health. That has not stopped an extremely vocal opposition
from funding poorly-designed studies and publishing misleading papers. We here at SciShow even reported on a study
indicating that GMOs caused an increase in cancer in rats. This study, led by a guy who was not-coincidentally
publishing a book on the topic that same week was published in a peer-reviewed journal and
was initially taken at face value. But cherry picked data, a lack of dose-response,
small sample groups, and a strain of rat that has an 80% chance of developing cancer in
its lifespan eventually combined to completely discredit the study. Of course, as with any new technology, it
can have unintended consequences; it can be controlled and monopolized and even weaponized,
so there is plenty of reason to keep an eye on the companies making these advances. But when considering the number of hungry
people on the planet, we have an obligation to explore every possible avenue to increase
crop yields and to decrease the amount of herbicide, pesticide, energy and water needed
to produce a crop. Traditional and advanced breeding methods
need to be a part of that, and so does genetic engineering. Thanks for watching this episode of SciShow,
and thank you to the people who pushed me to write up a more complete and accurate version
of this episode. If you want to continue getting smarter with
us, you can go to youtube.com/scishow and subscribe.
I remember Myles Power calling this guy out two years ago for using those debunked Anti-GMO studies. Well, better late than never
Three things still wrong.
-- NPR
As a big SciShow fan, i was really disappointed with the first GMO video they made. Good to see that they came around on the topic. Huge props to /u/ecogeek and the rest of the SciShow team for this.
Are you sure he's a reliable source? Myles Power really doesn't think he is. This incident was pretty bad, and as I recall he never apologized or anything, he just took down the video and carried on.
Well made production.
Nice happy meal size informational dump in a friendly, non-threatening, non confrontational manner.
Unfortunately the GMO crazies believe it with religious fervor. This isn't likely to help.
Thank you Myles Power for calling out Hank on his bullshit two years ago! I hope it made a difference at the end!
Are GM crops more likely to be sprayed directly with RoundUp? If so, does this increase RoundUp consumption, and does this pose an increased health risk?