"Cyclops Frog" - photomanipulation, not genetic mutation. Photo: Mark Rain, Creative Commons, some rights reserved

Apr 19, 2018 — Mutants are neither the creepy brain domes of science fiction, nor the smart-mouth turtles of the cartoons. Mutations arise all the time from environmental exposure to mutagenic substances and from imperfections in cellular reproduction. Martha Foley and Dr. Curt Stager talk change, genetic change.

Martha Foley: Let’s talk about mutants and mutations, because we see them in pop culture all the time - the Incredible Hulk, you know, the Mutant Ninja Turtles - what are mutants really, what are mutations, and how do they happen?

Curt Stager: Technically a mutation in the biological sense would be a change in the genes or change in the DNA that codes for the traits in a living thing. And so a mutant would be somebody who has mutations in them.

MF: Or a plant, or whatever.

CS: Or it could be any living thing that has DNA in it, if that DNA has been changed somehow, then you would say that would be a mutant.

MF: So it could be good or bad?

CS: Could be good or bad, and we often think of mutants like mutant ninja turtle — they’re some rare oddball or something — but actually, we’re all mutants!

MF: Speak for yourself!

CS: I freely admit to being an oddball. I’m a mutant, you’re a mutant, and anybody listening to us is a mutant. We’ve all got slightly different DNA, that’s how you do DNA fingerprinting when you tell each other apart those would all count as mutations that give us those mutations.

MF: And some of those are expressed, obviously, in our appearance. Right? How we walk, and how our bones go together, you know, specifically.

CS: Right. Some of them, like you say, can be positive, some can be negative, a lot of them could be neutral too. And a lot of it isn’t necessarily determined by the mutation itself, but it is also by the setting in which the thing lives.  Like you could imagine if you had a mutation on genes that control how you develop as an embryo. Let’s say you’re hand is developing as an embryo too. Normally what would happen is your fingers are developing but you don’t develop tissues in between your fingers, you kind of let that sit back. But what if the cells between your fingers decide to keep growing and you end up with webbing there.

MF: Then you can live in water world.

CS: Yeah! So, it depends on the situation. You might call it an adaptation in that case, if you live in a watery place, whereas in another place you might call it a birth defect or something like that.

MF: So what makes this happen?

CS: Anything that would change what’s in a DNA strand.

MF: Things that we eat, things that we breathe, toxic chemicals, all those things?

CS: All that stuff, and we often think I don’t want nasty chemicals or nasty radiation form human sources and things and that’s true but you really can’t avoid them because that stuff is out in the environment all the time. Radioactivity is natural; you get it from radon coming out of the ground, carbon 14 in the air and our bodies is all radioactive. Any of those things that can break a DNA strand or change the molecules in it would make mutations. And then of course the food you eat will often have chemicals in it, from plants or maybe plant defenses. Even water apparently can do it too! The water molecules can stick to the molecules that are making up DNA and change their structure a little bit.

MF: So it doesn’t have to be something toxic or intrusive, I mean, a water molecule can change your DNA?

CS: So you can see how it’s pretty much inevitable that we’re going to have some of these things happening, and we do have mechanisms that look for those and repair them ourselves, but sometimes those mess up too. So the mutations we see that cause evolution or cause diseases, things like cancer and stuff, are pretty much unavoidable, and therefore it’s inevitable that things are going to change over time too as those mutations build up.

MF: So this little change, does it have to be to the DNA to be a mutation?

CS: Yeah, the reason it has to be a change to the DNA is not because the DNA is involved in all these chemical reactions. The DNA is in charge of making all this stuff that runs your cells, say proteins, and you pass that DNA on from cell to cell in your body, and maybe even to make new people out of with reproductive cells.

MF: So something could affect you and make you sick, but you would get over that, this is something you’re not getting over?

CS: If it’s built into your cells from a mutation, the only way to stop it is to get rid of the cell, and sometimes your immune system does that, if it can tell it’s not acting right sometimes your own white blood cells will attack and kill it. But if that survives, then it can maybe change something in your body, or you can pass it on to a kid.

MF: Wow. Thanks very much, Dr. Curt Stager.