Glow-in-the-Dark Fish: Bright Idea or Environmental Threat?

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Audio Transcript:

Lisa Mullins: If you have an aquarium at home, you know just how cool it looks when you have something in the water that glows in the dark. It's even better when what's glowing in the dark is a fish. That's why a Texas-based company called Yorktown Technologies has created a line of genetically modified fluorescent fish. These GloFish have been around for a few years now, but there is concern that one of the company's fish, the Electric Green Tetra, could pose a serious environmental threat. Environmentalists worry that if one of the fluorescent tetras is ever released into the wild, it could threaten native fish species in Florida and elsewhere. Science journalist Adrianne Appel has written an article about this new GloFish in the Washington Post. Adrianne, first of all, this is the first genetically modified pet, is that right?

Adrianne Appel: Yes, the GloFish.

Mullins: What color do they glow?

Appel: A bright lemon green color.

Mullins: Sounds lovely. How do they get that? Can you explain how the fish are bred to glow this bright lemon green?

Appel: They've taken a gene from a fluorescent coral and inserted it in the DNA of what's called a Black Tetra fish, which is a fish native to South America.

Mullins: They're cute and look stunning but why would a fish like this have to be genetically modified when there are so many beautiful fish you see in aquariums anyway?

Appel: The aquarium fish industry in Florida alone brings in $70 million a year, and throughout the world it's a big industry, multi-billion dollar. And the Black Tetra fish, which is the base fish, is an aquarium fish on the market right now. It sells for three dollars. But the modified Black Tetra fish, the GloFish, sells for about eleven or twelve dollars.

Mullins: Holy smokes, and that's if you get just one.

Appel: Yes.

Mullins: And most people?

Appel: Most people will get a few, at least.

Mullins: So they can see them school.

Appel: Yes, exactly.

Mullins: So what is the concern that environmentalists have?

Appel: Environmentalists say we don't really know what would happen if the fish, which inevitably they will be eaten by larger fish.

Mullins: This is for people, pet owners, who say okay, enough of the aquarium and they toss the fish down the toilet, which is what happens.

Appel: Yes, typically they toss them into fresh water in Florida, and that's why there are now more that 25 species, non-native fresh water fish species, that live and thrive in Florida. So if this fish were eaten by a larger fish, we don't know if it might harm the larger fish or somehow upset the ecosystem. If the larger fish likes this new little fish, maybe it will stop eating other fish.

Mullins: And what happens if it breeds with another fish?

Appel: If a GloFish, Black Tetra fish, were to reproduce with a Black Tetra, some of the offspring would have the glowing gene.

Mullins: Obviously it gets passed on.

Appel: For multiple generations. Eventually it would be bred out but according to the company the gene would be passed on for multiple generations. One of the concerns of environmentalists is that it could be a kind of aesthetic pollution. Imagine yourself in Florida, you're enjoying yourself, out on a boat, on a canal, and maybe doing some fishing, or looking down in the water, and you see a bright, bright glowing fish, unnaturally glowing fish, and it's the GloFish.

Mullins: Some people would say, great! It's the GloFish! But others look askance and say what?

Appel: They would say this is pollution in my environment.

Mullins: Because it's not natural?

Appel: Yes.

Mullins: We should say that genetically modified fish are not widely accepted as being safe, certainly not in other countries where they've been introduced.

Appel: No, they're banned in Canada, and European Union nations banned genetically modified animals.

Mullins: On what grounds?

Appel: They take what's called the precautionary principle, that we don't know what may happen once a genetically modified animal is released into the wild, and that's a concern, is that these will inevitably be released into the wild.

Mullins: Adrianne Appel's article about the newest genetically modified GloFish, as beautiful as it is controversial, is on our website, You can also watch the GloFish glow on a video we're presenting. Adrianne Appel, thank you.

Appel: Thank you very much.