This is going to be fairly short compared to, you know, what modern genetics actually is, but this is just a brief overview. We'll talk more about some of the stuff that's happening, way, way, way down in the class. But this brief overview is just that genetics today is mainly used to study, you know, mutation and disease in order to improve medicine. Genetics is very big in medicine, and it's also very big in agriculture. So, we hear, you know, GMOs or things that are all the time in the news right now. Or gene therapies. All these things, all have to do with genetics in medicine and agriculture. And this is really what genetics is used for today. Outside of just science and just studying more about how the world works. But even then, most of that is for medicine. And so genetics today is really focused on understanding variation. And one major type of variation that geneticists study are things called single nucleotide polymorphisms or SNPs for short. You may have heard of these before in some other classes, but I'm just going to review them.
So what SNPs are, is they're small variations, usually one nucleotide, single nucleotide. So an A to a T or a C to a G, in an individual's genome. So how common are they? Well, there's this one great study in Iceland. They studied a ton of families and 78 children. And they found that in these 78 children, there were almost 5000 SNPs between them and their parents. So that means that there are nearly 5,000 single nucleotide changes, in these 78 children from their parents to their children. Their parents don't have them, but they do. And so, mostly, they also found that these variations come from the father, not necessarily from the mother. So why is that? So first, there's a huge amount of variation from your parents to yourself. You don't think about that. Generally, these are, you know, actual mutations. I mean, that's 5,000 mutations in 78 children. It's a huge amount of mutations that happen, and they're single nucleotide mutations. First, it's huge. And second, most of them come from the father. So you may ask why that happens. Well, mothers actually produce all of their eggs, during development. So when they are growing in their mother's womb, all the eggs are created then. So throughout their life, they release eggs, but they don't actually create them anymore. They're all created by the time they're born. The father, on the other hand, continually creates sperm throughout their life. Now, if you know anything about as you get older, certain processes start to, you know, not do so well. So I mean, obviously, aging. So our bodies don't work as well as we get older. This is true for sperm production. So for the father, they continually produce sperm, and so as they get older, they can introduce more and more mutations to their children. Now most of the time, these are, you know, harmless SNPs. They either don't do anything, or they may do something to help, but sometimes this can be actually fairly harmful to the child. So SNPs are a major source of variation in genetics and a major source of study. And so one example of a SNP that I really like to talk about is lactose intolerance or lactose tolerance. And so lactose tolerance, so that's the ability to actually continually drink milk and consume dairy products, past infancy. Lactose tolerant, so the ability to do that is actually from a SNP. And so, adults with, there are 2 SNPs in this certain region of the gene of a lactase gene. And lactase is just an enzyme that allows you to continually drink milk even though you're an adult. Those people with these mutations, so with the SNPs, can digest lactose. That means they're lactose tolerant. The people without the mutations, they are the lactose intolerant ones. And so, actually, if you can digest milk that means that you have a mutation that allows you to do that, whereas the people who cannot digest milk past infancy, the lactose intolerant ones, are actually, the normal ones among us. So yay for lactose intolerance. And so here's just an example of a SNP.
There's been a lot to do with technology and the development of technology in modern genetics. Now, I'm not going to go through all the different types of technology that have been created just for genetics, but I am going to mention some of the few ones that you may see in your book. First is biotechnology, and that's going to be manipulating biology or biological processes for industrial purposes. So a good example of this that you may read about is Golden Rice. So, rice normally doesn't really have that much vitamin A or beta-carotene in it, which is a precursor of vitamin A. But rice is consumed around the world in areas where people really need vitamin A. So scientists have, sort of, manipulated the rice's biological processes in order for it to produce beta-carotene, which when consumed by humans, especially in areas that need it, this will be converted by the body to produce vitamin A. So biotechnology has, you know, sort of, manipulates, it can manipulate organisms and manipulate processes. But it manipulates these biological processes for some type of industrial purpose, whether that's adding vitamins to things that it needs, to making bacteria make certain proteins so you can use them in the lab or in medicine. All of these things are examples of biotechnology. Gene therapy is when you clinically transfer genes into individuals who have a mutation. So their genes aren't working, they're mutated. So you can transfer those into the patient, and then in hopes that that having that new gene will actually improve the patient's condition. You have proteomics, and this is going to be the study of the proteins in a cell under certain conditions at a certain time. So every second that you are alive, your protein composition in every single one of your cells is changing. And your protein composition in each one of your cells is different. Your skin cells have very different protein compositions than your brain cells. So proteomics attempts to take all of those cells at every, you know, time the point that they can and determine, you know, what set of proteins make these skin cells? What are these proteins doing? And how, you know, can we use that information for medicine or agriculture? Anything to make our lives better. Bioinformatics is, great for the math people out here. And this uses software some kind, to help analyze and store this large breadth of data that geneticists today have to deal with. So we have all of these proteomics that, you know, that's a huge amount of data to know what your proteins are doing in all of your cells in your body at every second of every day. That's a huge amount of information. And that's just the proteins. That's not including the DNA. It's not including the RNA. It's, you know, not including all these things that are produced. It's just including the protein. So bioinformatics takes that information from the genes, the RNAs, the proteins, everything, and they analyze it for information, so that we can use that. And then we have model organisms, and these are organisms used to study the basics of genetics. These are things like fruit flies that you may, hear about you're going to hear about a lot in this class, which is, Drosophila melanogaster. Those are fruit flies. You have plants. You have worms. You have mice. All of these organisms, are used in laboratories to study these genetic basics, to study medicine and genetics, agriculture and genetics. It's all super important. But this technology is super crucial in modern genetics today. So, with that, let's now move on.
