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Introduction to genetic engineering

Genetic engineering, although a recent concept, has roots in ancient human practices like selective breeding of animals and plants. Today, recombinant DNA technology enables precise gene manipulation, creating genetically modified organisms (GMOs) with enhanced traits. While offering benefits like robust crops and new medicines, it raises bioethical concerns, especially regarding human genome modification. Created by Sal Khan.

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  • starky sapling style avatar for user Ariana
    Would the steriods that atheletes take, count as genetic engineering?
    (12 votes)
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    • duskpin tree style avatar for user Nicole Gong
      Genetic engineering is the process of modifying an organism of a genetic level- for example, inserting or modifying a gene into an organism is genetic engineering. However, steroids are simply compounds (like vitamins or hormones) that can affect bodily function- they don't modify your body on a genetic level!

      athletes take anabolic steroids, which is basically artificial testosterone to make you swole. These don't modify your DNA in any way, though they do have some pretty awful side effects to your own body. In another way of thinking, if you do take steroids you can stop worrying about passing its effects onto your children (though anabolic steroids have been linked to decreased or an absence of sperm).
      (25 votes)
  • blobby green style avatar for user haseebehsan36
    Is it possible to insert DNA of One species into Another Species?
    (11 votes)
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    • starky tree style avatar for user snowman334
      Absolutely, these are called transgenic organisms. There are a lot of great examples of this, such as Bt Corn, in which a gene from the bacterium Bacillus thuringiensis (Bt) is inserted into the genome of the corn plant. This allows the plant to produce a delta endotoxin, which is extremely fatal to certain insects, but has virtually no effect on mammals.

      Of course, there are a lot of considerations to this process. In addition to the target gene that you want to express in the new host organism, you also have to include genes which would regulate the expression of the target gene, and other genes which may be necessary for proper post translational modification of the final protein product, so that it is functional.
      (16 votes)
  • blobby yellow style avatar for user Gryffin Flowers
    If type 2 diabetes can be genetically inherited and type 1 is not, then can genetic modifications used to create insulin only be used on patients with type 2 diabetes or could genetic engineering be used on both type 1 and type 2?

    Also, what is the day-to-day job description of a genetic engineer?
    (8 votes)
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    • starky tree style avatar for user snowman334
      Insulin is insulin, and we can use genetically modified bacteria to produce insulin that can be used for either type of diabetes (although type 2 diabetes often does not require insulin injections).

      But you're not thinking big enough. Theoretically, we could use genetic engineering, or better still, genome editing, to remove or correct all genetic traits which lead to type 2 diabetes.
      (10 votes)
  • blobby green style avatar for user labhjeevan13
    how do we get a certificate for it?
    (6 votes)
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  • blobby green style avatar for user tboene16238
    How do they do DNA testing
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  • stelly orange style avatar for user madhav48719
    At gmo disadvantages are really tough to see for , as for centuries we havent seen any potential harms , even though with tech increment we have the potency to take such actions by calculating risks , then to it would have sidee-ffects rather then bad use ?
    (1 vote)
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  • leafers sapling style avatar for user SnowyRawrGamer
    Would it be possible to mate an animal and a plant? If not, then why not?
    (1 vote)
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  • male robot hal style avatar for user adzilc8
    check out change agent by daniel suarez
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Video transcript

- [Instructor] The idea of genetic engineering is something that we associate with the 20th century. We didn't even know that genes were actually the mechanism of heredity until the middle of the 20th century. And the direct modification of genes for some purpose really didn't even start happening until the 1970s. But it's worth noting that human beings have been, in some ways, influencing the genetics of organisms for a very, very, very long time. For example, in nature you have things that look like this. We call them wolves. But today in our lives, we also have things that look like this. Now these dogs did not come about naturally. They came about from many generations of breeding, of human beings taking things that started off looking like wolves or foxes, and selecting for certain traits. They might have selected for traits that maybe they're small, and they look more like puppies, even when they're full grown. Or traits that they are more docile. They're more likely to listen to what a human being says to do. Or traits that they're good at killing rodents, or whatever else it might be, and over time, repeated selection of those traits led to what we see as these different breeds of dogs. So even though human beings were doing this for hundreds and thousands of years, they were influencing what DNA gets passed on from one generation to another. They didn't know about the actual genetic code, but it was a form of genetic manipulation nonetheless. Similarly, if you look into the plant kingdom, when you go to the store and you see that sweet apple, things like that might not have existed in the form that you see them today. It is very likely, in fact most agricultural products, people might have found wild apples, and we could be talking thousands of years ago. They might have found wild apple trees. Let me draw a quick apple tree here. And they might've found that the apples were a little bit sour, and small, and hard to eat, and hard to digest, but over time, people selected the trees that had sweeter apples, that had larger apples, and made the conditions so that they were more likely to reproduce. So over time, you got larger and sweeter apples like the type that you see at your store. And as I mentioned, most agricultural products that we have today are the result of hundreds or thousands of years of this type of breeding. So even though that might not be the formal definition of genetic engineering, which typically is referring to something like gene modification, which we've only been able to do in the last few decades, human beings have been doing some type of influence on organisms' DNA for a very, very long time. But with that said, in the last few decades, we've been able to become much, much more precise with influencing DNA through genetic engineering. In other videos, we'll go more detail about how that is done, but you have this idea of recombinant DNA, where you could take genes from one organism and put them in another organism. And you might say, why is this useful? Well let's say there is a tree you wanna grow. Let's say it's an apple tree, but it's very susceptible to a certain type of disease, and if that disease hits, you lose all of your crop. But what if you could insert into the DNA of that apple tree maybe a gene that makes it more resistant to that disease? And this is what people actually do today. So they will insert DNA, and it could be from some pretty wild things. I've read stories about inserting insect DNA into a plant so that it will be more robust in some way or another. Now this idea of recombinant DNA and genetically modifying food, this is often known as a genetically modified organism, this is somewhat controversial. Many people say, hey this is good. It allows us to produce more robust foods. In fact, part of this recombinant DNA, inserting DNA into something else, it might make it more nutritious. It might provide for more vitamins. But other people would argue that, hey we don't know exactly what all the repercussions of what we're doing will happen. We might think it's helpful, but when you're taking DNA from one organism and putting it into another, how does that affect the nutrition, or the long-lasting effects of eating that over time? So this is something for you to think about. And we're starting to go, when we start asking these questions, into the field of bioethics. As we have more and more control over the genome, and especially, as we'll see, the human genome, there's questions that we have to ask about is it good, or is it bad? But going back to this idea of genetic engineering and recombinant DNA, other things that you could do is you could, let's say that we need to produce insulin for diabetics. Well, maybe you can take a bacteria cell, and insert into the bacteria cell the gene that helps produce for insulin. And then, all of a sudden, that bacteria cell can become an human-insulin-producing factory, so that we could have more insulin for diabetics, that this insulin could then be harvested. That is a use of recombinant DNA. And so we really are going into an interesting period in humanity. For many thousands of years we were breeding things, but now we're learning to manipulate things at a very fine-grain level. And it makes us ask all sorts of questions. There are likely to be some very good things we can do. Produce new medicines. Produce more robust crops. But there are also questions about what are the side effects? And the bioethics get really interesting when we start thinking about modifying the human genome itself. Because when you're modifying genetics, you're not just modifying one organism, you're modifying all of their offspring. You're modifying the genes that exist in the gene pool. And so some very good arguments for modifying the human genome are correcting diseases, some things that could be very serious. But over time, things might, people might say, hey I wanna be a little bit taller, or I want a certain hair color, or I want straighter teeth. Or they might say, I want a child who has this trait or that trait. So things get very, very interesting the more we think about how genetic engineering may be used.