GloFish might sound like a quaint option for a pet, plucked - or perhaps netted - from a salty sea somewhere.
But it is actually a zebrafish that has been altered, genetically, so it contains a fluorescent protein gene. Place it under an ultraviolet light in a fish tank and it will glow.
Such a futuristic fish might form a suitable snack for Mr Green Genes, a genetically engineered glow-in-the-dark cat.
While some people might find creatures like these perfectly suitable as household pets - who wouldn't want to avoid stepping on kitty's tail in the middle of the night, after all? - what they may not know is that such animals have been part of research projects. The scientific aim has been to help endangered species, in some cases, and to fight diseases through gene therapy in others. Over time, the hope is, scientists may be able to find a way to insert healthy genes into people while removing potentially dangerous or unhealthy ones.
As a journalist and writer for the blog network of the Public Library of Science in the United States, Emily Anthes has long written about critters that glow. She is also the author of a book released earlier this year called Frankenstein's Cat: Cuddling up to Biotech's Brave New Beasts.
Here, Ms Anthes discusses the scientific - and commercial - potential of glowing animals:
Why have scientists spent so much time playing around with fluorescence genes?
Fluorescence genes are incredibly useful tools for basic research because they provide easily visible signals to scientists. For instance, scientists can engineer animals in which only certain kinds of cells or tissues glow. Researchers can then observe these cells more easily and track them over time. Or scientists can create animals that only glow when certain proteins are being made, allowing them to see when and where protein production is happening.
What were some of the first examples of animals that could glow?
Scientists first isolated the GFP [green fluorescent protein] gene in the 1990s, and then began moving it around the animal kingdom, but I'm not sure which animals were first. The scientists who "discovered" it subsequently won a Nobel Prize.
Why do you think consumers have been so fascinated with glowing animals, such as GloFish?
Glowing animals are strange, unusual and [to some people] also cool. They're like nothing else on the marketplace, and humans have a history of seeking out new and exotic animals. Glowing pets are just a modern, biotechnological version of that.
How great is the business potential for glowing pets in the marketplace, and what remains the biggest hurdle that prevents growth for this segment?
The biggest hurdle is the so-called "yuck factor". That's the instinctive aversion we sometimes have to biotechnological products. It's not necessarily based on logic, but the visceral, gut-level disgust that some people will feel when looking at, say, a neon cat, can be powerful. There's no doubt that some consumers will find glowing cats creepy, and I suspect the market for glowing cats and dogs will be considerably smaller than the market for glowing fish. My hunch is that GloFish don't seem so strange to us because there are plenty of species of fish that are naturally neon. On the other hand, a neon cat or dog is clearly an oddity.
Some people might find this work unethical. What are some of the concerns people have had, in your experience?
The objection I hear most often is that making a glowing pet is a trivial use of technology. In fact, this seems to be the primary reason that California decided to ban GloFish. The experts concluded that the fish posed virtually no risk, but the state's fish and game commissioners thought that because the fish were so frivolous, they represented an unethical use of genetic engineering.