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  • The 1840s were a bleak time in Irish history. Imagine one in every

  • six people you know slowly painfully dying of starvation or disease. Then in

  • the next few years, as many people leave the country and never come back. And over

  • the next few decades the number of people in your town is half of what it

  • used to be. During the Irish Famine, 1 million people, or about 15% of the

  • population died. Another 1.5 million people fled the country in its

  • immediate aftermath leading to a permanent decline in the Irish

  • population. Ireland and the whole world was changed forever

  • due to one persistent devastating fungus. The late blight or phytopthora

  • infestans is a fungus that attacks the potato plant leaving the potatoes

  • inedible. The fungus spores spread easily in the wind

  • and quickly infect neighboring plants. It was particularly disastrous to Ireland

  • due to the potato being hugely relied on for food by the rural poor. By the 1850s

  • the widespread blight eventually ran its course

  • but it did not disappear entirely. To this day blight remains a significant

  • problem for potato and tomato growers that has to be battled year after year.

  • 160 years after the famine, late blight is still a five billion dollar problem

  • for the global potato industry. Some potatoes can be bred to have some

  • resistance to the fungus but this can take decades. So the reality is that

  • farmers need to spray their crops with lots of fungicide every week

  • indefinitely. But in 2015 a breakthrough occurred - a new variety of GMO potato was

  • developed that can resist the very blight that killed so many. Using blight

  • resistant genes from wild potato plants, scientists precisely adapted a version

  • of the common potato to withstand the fungal disease. This GM potato, called the

  • Innate Potato, can save farmers huge amounts of time and money and can reduce

  • the amount of environmentally damaging pesticide that gets sprayed on the

  • fields - up to eighty or ninety percent. And so naturally Ireland with its

  • history of massive crop failure killing a million people and its commitment to

  • green agriculture says - nope let's ban it and in fact let's try to ban all GMOs.

  • Okay so what is going on? "so it's made in a laboratory and more often than not

  • they're inserting viruses or bacteria into these plants" "what you need to know

  • is that the process itself is flawed." We've all probably seen debate like this.

  • GMOs are bad, they're bad for you, they'll give you cancer, they'll give the world

  • cancer, and that they are literally the devil. Yet others say GMOs will end world

  • hunger, stop climate change, and that they're completely harmless. There are so

  • many videos articles and interviews on both sides of this and the amount of

  • unresearched unscientific claims out there to sift through is infinite.

  • There's an ever-present sense of hysteria when discussing anything to do

  • with GMOs and this public sentiment informs government decisions for better

  • or for worse...usually for worse. But like most things, the issue of GMOs is not as

  • black and white as many people would lead you to believe. GMOs are not what

  • will save the world nor are they what will destroy it. Before we get into

  • whether or not GMOs are good or bad, let's first understand what they even

  • are. Genetically modified organisms are organisms that have been altered using

  • genetic engineering methods. The key steps involved in genetic engineering

  • are first to identify a trait of interest. Then isolate that trait, insert that

  • trait into a desired organism, and then propagate or breed that organism. Most of

  • the GMOs on the market today have been given genetic traits to improve their

  • quality, provide tolerance to drought, or to provide protection from pests like

  • the GM potato I mentioned before being resistant to fungal infection. Another

  • big example of this in the world of GM foods is insect resistance. BT maize for

  • example is a strain of insect resistant corn. Corn farmers are challenged with a

  • number of pests, but the most damaging are caterpillars that are stalk borers,

  • ear or leaf eaters, and beetle grubs that eat the roots. The European corn borer

  • for example was nicknamed with the billion dollar bug because it costs

  • growers over a billion dollars annually in insecticides and lost crop yields. For

  • years farmers have largely relied on chemical insecticides to protect their

  • crops, but in 1996 farmers were introduced to genetically engineered

  • corn with resistance to the European corn borer.

  • These genetically modified plants produce proteins derived from the soil

  • bacterium bacillus thuringiensis, hence the name BT maize. The proteins that are

  • produced by the bacteria are crystal proteins which are toxic to caterpillars

  • like the corn borer, and are introduced into the corn through

  • a process called transgenesis. The first step in this process is identifying an

  • organism with the desired trait - in this case something that is toxic to

  • caterpillars. Around a hundred years ago silkworm farmers noticed that

  • populations of silkworms were dying and scientists discovered that a naturally

  • occurring soil bacteria was causing the deaths. Scientists now know that these

  • soil bacteria that are toxic to silkworms are also toxic to the European

  • corn borer. The next step in the transgenesis process is to extract the

  • desired DNA out of the bacteria. This is accomplished by taking a sample of

  • bacteria containing the gene of interest and taking it through a series of steps

  • that separate the DNA from the other parts of the cell and isolate the gene

  • of interest, usually using cloning vectors. The next step is gene insertion,

  • in our case getting the BT gene into the corn. Since plants have millions of cells

  • it would be impossible to insert a copy of the transgene into every cell.

  • Therefore tissue culture is used to propagate masses of undifferentiated

  • plant cells called callus, which are kind of like stem cells in humans. These are

  • the cells where the transgene will be added. The transgene is inserted into

  • some of the cells using various techniques, such as with a gene gun or by

  • electroporation. The main goal of these methods is to deliver the transgene into

  • the nucleus of a cell without killing the cell. The cells can then be treated

  • with a series of plant hormones allowing it to grow into an entire plant. You now

  • have corn crops that contain their very own insect resistance. The huge benefit

  • of this is that one, the corn crops don't get destroyed by these caterpillars and

  • two, that less insecticide is needed to combat them. Studies have shown a pretty

  • indisputable decrease in insecticide use when BT or similar crops are planted. GMO

  • crops can also stave off malnutrition in many parts of the world. Vitamin A

  • deficiency has been recognized as a significant public health problem

  • continuously for more than 30 years. The problem is particularly severe in

  • populations where rice is the staple food and diversity of diet is limited, as

  • white rice contains no micronutrients. Vitamin A deficiency is the leading

  • cause of preventable blindness in children and increases the risk of

  • disease and death. Mirroring our Irish Famine example from before, these deaths

  • are caused by diseases which thrive in malnourished people. To combat this,

  • scientists engineered what is called Golden Rice. This rice produces

  • beta-carotene which is the precursor of vitamin A. It's the same pigment found in

  • carrots and just one cup of golden rice per day per person can prevent vitamin A

  • deficiency and has the potential to save thousands of lives. It's never possible

  • to prove a food is completely a hundred percent safe .We can only say that no

  • hazard has ever been found to exist. And there have now been over 500 scientific

  • studies looking for and failing to find conclusive risk to human health from GM

  • crops. Take the example of crops containing insect resistance - many

  • studies have confirmed that BT toxins can only work in alkaline environments

  • and require specific enzymes and receptors in the insect gut to cause

  • toxicity. Humans have very acidic stomachs and lack these enzymes and

  • receptors and so are not affected by the BT crystal protein. Other ways scientists

  • test GM foods before releasing them to the public

  • are by simulating the behavior of GM proteins in the human gut to see whether

  • the proteins degrade during digestion, or more conclusively, to test the GM crop on

  • animal models like lab rats. The rats are first fed a single meal of the GM crop

  • or protein to test for acute toxicity. Then the rats are fed repeated meals of

  • GM food for 90 days and sometimes up to a year to test for chronic toxicity,

  • which is the type of harm that only appears with repeated use. Despite many

  • studies like this failing to find anything harmful about GMOs there is

  • still radical opposition. In 2013 anti-gmo activists, heavy air quotes

  • there, invaded and destroyed a field trial for Golden Rice in the Philippines

  • setting the study back months and jeopardizing the technology's

  • implementation. Ireland as we mentioned before is trying to approve blanket

  • restrictions on GMOs citing the need to maintain their international reputation

  • as a green sustainable food producer. So all this leaves many of us thinking why

  • are people so opposed to something that seems to be so good for the world? Is

  • there any basis for this? While the misinformation that spread seems endless

  • and the number of bogus claims that circulate are frustrating it would be

  • disingenuous to pretend that the rise of GMOs has only been a good thing, but not

  • because of the reasons most anti GMO groups on Facebook and Irish politicians

  • are claiming. While things like BT crops do reduce insecticide use there is another

  • side to the coin. One of the most common types of GMO crop around the world are

  • ones that are resistant to herbicide, specifically glyphosate. Roundup Ready is

  • the Monsanto trademark for its patented line of genetically modified crop seeds

  • that are resistant to its glyphosate based herbicide Roundup. So in an

  • opposite way to the BT crops we discussed before Roundup Ready crops

  • mean farmers can use more herbicide on their crops. One study shows that on

  • average adopters of GE glyphosate tolerant soybeans used 28% more

  • herbicide than non-adopters. Another study says that globally glyphosate use

  • has risen almost 15 fold since Roundup Ready crops were introduced in 1996. And

  • roundup is not exactly good for people or the environment.

  • Glyphosate can leak into soil and surrounding water affecting wild plants

  • and animals, which ultimately can hurt the food chain. And recently the World

  • Health Organization has declared roundup to be probably carcinogenic, after years

  • of debate around this point. Other research points to its possible effect

  • on mitochondrial and brain function and animal models. This research is still

  • being carried out and there's increasing concern about the chemical combinations

  • used in commercial weed killers and their long-term impacts especially for

  • the people using it every day. And right now Monsanto is embroiled in lawsuits

  • with people alleging that Roundup caused their cancer. A jury in California just

  • awarded a couple two billion dollars in a verdict against Monsanto which is the

  • third in a string of recent court decisions involving claims that the

  • company's Roundup weedkiller caused their cancer. And while a jury is not a

  • scientific panel of experts and there's much debate around the truth of these

  • cancer claims, the money was awarded on the basis that Monsanto manipulated its

  • own research, colluded with regulators, and

  • intimidated scientists to keep secret the cancer risks of glyphosate. We could

  • make a whole video just about the shady business practices of Monsanto, so it is

  • not implausible to think that Monsanto is capable of something like this. So as

  • we can see this is a nuanced conversation and any doubt people may

  • have about this hugely complicated subject can easily be exploited. Pew Polls

  • have found that some 49% of US adults surveyed said that foods with GM

  • ingredients were worse for one's health up from 39% just two years ago. Another

  • Pew poll published in 2015 found the biggest gap between the public

  • and the experts on the GMO issue that on any other area of science controversy,

  • including vaccines, climate change, and nuclear power. And to make things worse

  • evidence has emerged that Russian bots and trolls have been making great

  • efforts to spread anti GMO memes among Western audiences in order to undermine

  • public trust in science. Yes we should criticize Monsanto and similar large

  • corporations for shady and damaging business practices of which there are

  • many. Yes we should question what role GMOs should play in our world and study

  • the effects rigorously. But to say GMOs are harmful is like saying the Internet

  • is harmful. Yes it can be used in harmful ways but it also has the potential to do

  • absolutely wonderful things for millions of people. To oppose GMOs unequivocally

  • as so many do is simplistic and misguided. Ireland's push to prohibit the

  • cultivation of genetically modified crops for example is completely at odds

  • with the country's ambitions for climate action, and it is deceitful to equate GMO

  • cultivation free status with green and sustainable. Gene edited crops have the

  • potential to cut climate emissions in agriculture and reduce harmful chemicals

  • in the environment as long as they are regulated properly. A recent report

  • highlighted how Ireland is ranked second worst in the EU for tackling climate

  • change and will not meet its EU 2020 commitments. Yet the push to blanket ban

  • GMOs continues as Ireland turns away from a major tool in the toolbox to help

  • tackle this problem. And if such politicians had any sense of irony they

  • might take a look at the people across the world

  • from vitamin A deficiency or the crops failing year after year because of

  • drought in East Africa and see the parallels between what is happening

  • there and their own country's history. But instead their moral posturing will

  • add to the increasing tide of voices drowning out sensible conversation about

  • this technology. Like plant geneticist Pamela Ronald has said, what scares me

  • most with the loud arguments and misinformation about plant genetics is

  • that the poorest people who most need the technology may be denied access

  • because of the vague fears and prejudices of those who have enough to

  • eat. The future of our society is linked with the future of food and genetic

  • engineering of our crops is just one of many ways we can sustain the world's

  • growing population. You can learn more about different food and farming

  • solutions from vertical urban farming to producing more insect protein in a

  • documentary titled "The Future of Food" on CuriosityStream. CuriosityStream has

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The Truth About GMOs

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    joey joey に公開 2021 年 06 月 09 日
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