Short Stuff: Genetic Mutations | STUFF YOU SHOULD KNOW

[Music]. Hey, and welcome to the short stuff. I'm. Josh and there's Chuck. And this is. Short Stuff, the mysteries of genetic. mutations edition. That's right. Because. uh we're going to talk about the X-Men. Yeah. A m a mutation. I mean, I don't. know if it would help you join the. X-Men, but there are mutations that. alter people sometimes in positive ways. We usually associate it with negative.

stuff like a a congenital disease or. something. A lot of them are neutral. I. think actually the vast majority are. neutral. They don't really have any. noticeable effect. Some are beneficial. Lactose intolerance, immunity to. malaria, uh when someone's vestigial tail turns. into a glorious full tail. Those are all. beneficial genetic mutations, but all of. them share something in common. and that. is that the the re replication of the. person's genome had some sort of error.

while it was being copied. Is lactose. intolerance a beneficial? No, lactose. tolerance. I think you I thought you. said intolerance. Oh, I'm sorry. Um, yeah. So, lactose intolerance is. apparently the the the base line, the. default. Lactose tolerance is from a. genetic mutation. All right. Uh, well, let's get into this. Let's talk about. DNA. uh or deoxy ribboucleic acid as we all. like to call it. Such a great word. around the campfire. Um that's a.

molecule that's going to carry genetic. material. I almost said mutation uh when. you're developing uh as a as a future. human. And uh structurally, I think. we've all seen the um if you've seen. Jurassic Park, you've seen what these. double uh this double helix looks like. It's a long molecule comprised of. nucleotides and uh there been you know. there's two strands to that coil that. form the double helix uh that kind of. wind around each other and that's that's.

what the DNA um the full DNA what would. you call it just molecule looks like the. genome yeah the molecule DNA is a. molecule and you said it man it is long. apparently if you stretched it out it. would be about 2 meters or six feet tall. if you could figure out how to stretch. it out. It's amazing. And it's made of. 3.1 billion base pairs of nucleotides, thymine, cytosine, guanine, and uh.

adinine. And adinine goes with thymine. and cytosine goes with guanine. And you. put all that together, just with those. combinations, you have a a a galaxy of. different um code that's embedded into. the DNA that serves as how like it tells. the rest of your body, each cell, what. it's supposed to do and how to do it. And usually that has to do with. expressing proteins. Yeah. uh and you. know like you mentioned as these cells.

divide and the DNA is making copies of. itself uh there might be errors here and. there and that's where those mutations. come from uh in the egg and if there in. the egg and sperm cells that those are. going to be uh passed on to the next. generation. So that's a genetic mutation. that's going to uh carry on and cause. disease or genetic disorders. Uh you can. also have uh what's called a somatic. mutation and that only affects you. It's. not inherited by your future kids. Right. Exactly. Um, so really the big.

problem is genes like a gene not being. replicated correctly. And a gene is just. a stretch of nucleotide base pairs along. your genome that's that together shows. how to encode a protein. It's the. instructions to how to do a specific. thing. And again, it's just a a segment. along your your DNA. Um, and when that. stuff gets copied, if there's any kind. of error, like say you match up a an. adenine to a cytosine, it it's going to.

prevent that that cellular process that. that whatever the gene is telling the. cell to do to not be able to be. performed correctly, hence a mutation. Yeah. And our cells are constantly uh. copying themselves, either replacing old. cells or damaged cells. And when that. happens, when they're doing that copy, that doublestranded DNA is going to. split into the two parts and each strand. is copied on its own and then they come. back together. And when that happens,

there can be errors. Uh the good news is. uh it's approximately one in every 100. million replications this happens. So. that's a you know, that's a pretty good. statistic to to have in your hip pocket. Um the other good news is, uh DNA knows. what it's doing. So, it generally knows. when an error happens and they try to. and often can repair and correct that. before any problems arise. Yes. Um, I. think that's a pretty good place to take. a break, Chuck. So, let's take a break, Chuck. Let's do it.

[Music]. truck. Learning stuff is fun with Josh. [Music]. [Applause]. and Okay. So there's basically two ways. that you can uh that a genetic mutation.

can develop. The cell replication which. we've talked a lot about and then. environmental influences. Um and there's. actually different ways it can happen. even during cell replication. Um there's. totic shifts which is where the. nucleotide itself undergoes a a quick. chemical reaction to where suddenly. adinine turns into um I don't know. silver just for a second and then it. eventually turns back. But if that if. that adinine nucleotide is being copied.

at that moment you're going to have a. silver um nucleotide in your DNA and. silver just don't work when it comes to. making proteins. Yeah. So that's sort of. due to bad timing. Uh, another thing. that can happen as far as those errors. go is what's called mispairing. And was. this a how stuff works article? Yes, it. was. Yeah, they they did a pretty good. job of putting this in terms we could. understand. If you imagine those two DNA. strands that work together are zipped. together like a zipper, sometimes that.

zipper doesn't align and get stuck in. it. Oh my god. And that that can happen. uh when the DNA is getting zipped back. up and that can cause parts of it to be. skipped over or maybe something added. that shouldn't be right. And then um the. third way that a mutation can happen. during replication is what's called. jumping genes cousins of jumping jacks. Um and that is where so these genes are. normally I don't understand this fully. but genes which again are just stretches.

of code on your DNA can actually move. They can change positions. They can. change places. Sometimes they replicate. themselves and and the the replicant. goes and embeds itself in another. segment of your DNA. And if it does so. in a gene, another gene, then it's going. to mess up that gene's ability to per to. perform its function. Did not know that. that was a thing. Did not either. Had. never heard of jumping jeans. I've heard. of jumping beans and jumping jacks, but. never jumping jeans. Very nice. Uh so.

that's the the ways uh that can happen. as far as like an error occurring in. your body, right? Uh on a cellular level. you mentioned external factors. Um one. of the big ones and I didn't know to. this extent even is um is radiation and. you might be thinking like yeah so you. just don't get x-rayed uh when you're. pregnant like that solves everything. right? uh that's not necessarily the. case because UV radiation can be a very. big cause of uh mutations. Um.

specifically um when it it's called like. a sunburn on your DNA. Um if you're have. too much UV radiation uh you can they. can form something called uh how would. you say that? I'm going to say. perramdine dimers. Perramitine dimmer. And I looked I was like is that a. misprint? Is it supposed to be dimmer? And nope. No, it's dimmer. uh and. especially thymine DRS that can distort. that DNA structure and that's sort of. like uh a sunburn on the DNA and that.

happens when a couple of DNA building. blocks uh are stuck together and that's. often times caused from you know sun. exposure. Yeah. Um there's also uh. chemical factors too which are basically. biological or environmental factors. Essentially what it is is there's. different kinds of chemicals that can. make their way into the DNA in the. nucleus of a cell and just mess with it. Sometimes they mimic nucleotides and.

they get pulled in uh like uh like just. some guy walking down the street getting. pulled into the Jimmy Fallon late night. show because they couldn't get enough. people to fill seats. That can happen. during DNA um reproduction replication. And when that that nucleotide that. didn't mean to be there uh gets entered. into that the um the new code of DNA, it. again problems arise. That's mutation. The problems arise when they have to sit. there and watch Jimmy Fallon.

Oh man. Oh boy. I'm going to hear it. Uh. there also biological factors um like a. virus uh can cause that can get in the. DNA. Yeah. And that can lead to. mutations. Uh and then there's some. other environmental stuff as well, right? Yeah. Um deanimating agents, they. actually remove parts of our DNA. Um. substances like stuff found in cigarette. smoke can stick to DNA like so much tar. um and change the shape of the DNA. Essentially, you don't want anything.

going anywhere near your DNA. And if. there's something that happens and it. happens on an important gene, that. mutation is going to produce some sort. of problems down the line. But our body is actually really really. good at either preventing these errors. or correcting them when it finds them, which is just mind-boggling to me. Yeah, it it's super cool uh that our body can. do this. Uh sometimes it's like a it's. called a direct fix. And these are these. are just small little errors like uh.

they likened it to a a road crack and. they also likened it to just a quick. patch on that road. The cell just. directly fixes it. Super quicklike. Yeah. And we should say the cell the the. the yeah the cell that's transcribing. the DNA um is aware of it because there. are different um different molecules. that proofread the the newly created DNA. to make sure it matches the original. Amazing. Yeah, it is. So if they find a. mismatch, if they find um just some.

stretch, it could be big, small, whatever, they'll actually cut it out. excision. They'll digest it and then. they'll reproduce the correct version of. it and and then connect it to that part. that they um cut out of the DNA and then. zip it together. And if it's uh if a. whole section of DNA gets gets damaged, they can go to other another DNA strand. and say, "Hey, I'm glad you're here. because we're going to use you now to. come fix this other strand." Yeah. Thank.

God you're here. They were about to pull. us into Jimmy Fallon and we needed. something to do. That's a of said thing in my house. Thank god I was here uh because u I know. we mentioned War of the Roses the movie. how it holds up. That's one of the great. lines from War of the Roses when uh they. are separated but Michael Douglas is. still in the house and the Christmas. tree catches fire and he runs downstairs. and puts it out and screams, "Thank God. I was here." And I say that a lot and. just whenever anything dumb happens that. I saw for the family, I go, "Thank God I.

was here." That's great. That's a great. thing, man. Chuck, you everybody loves. Chuck for reasons like that. Not. everybody. Just like Raymond. All those. people can go soak their heads. Oh, okay. Thank you. Um, well, since I think. we're out of stuff to talk. about, short stuff is out. Stuff You Should Know is a production of. iHeart Radio. For more podcasts, iHeart. Radio, visit the iHeart Radio app, Apple. Podcasts, or wherever you listen to your.

favorite shows. [Music].