Zebra Fish and Their

Glow In The Dark Siblings

We were in Morgantown yesterday and on the way home I stopped by Eastern Pet Supply in Bridgeport to pick up a few zebra fish for the aquarium. Zebra fish or zebra danio, Danio rerio, are freshwater fish belonging to the minnow family. They are a popular aquarium fish and is also an important model organism in scientific research.

My zebra fish were about a dollar each. I looked at the next tank and saw colored zebra for eight dollars each. These were the genetically designed zebra that glow in the dark.

In 1999, Dr. Zhiyuan Gong and his colleagues at the National University of Singapore extracted the green fluorescent protein (GFP) gene from a jellyfish that naturally produced bright green bioluminescence. They inserted the gene into the zebrafish genome, causing the fish to glow brightly under both natural white light and ultraviolet light. Their goal was to develop a fish that could detect pollution by selectively fluorescing in the presence of environmental toxins. The development of the always fluorescing fish was the first step in this process.

Shortly thereafter, his team developed a line of red fluorescent zebra fish by adding a gene from a sea coral, and yellow fluorescent zebra fish, by adding a variant of the jellyfish gene.

When Dr. Gong presented a slide of his glowing fish at a conference, it captured the interest of a fish produce company. (Oh, no surprise here!) Seeing its value in the fish sales market, they agreed to fund the professor’s experiments in exchange for use of his techniques. The rest, as they say, is history. Or history in the making, as the story is still unfolding.The glowing fish, named TK-1 by its creator, is being sold in Bridgport and I certain other W.V. locations. Not everyone is in favor of marketing the fish, and considerable debate is raging over the ethics and safety of marketing genetically altered fish.

GloFish are sold in bright red, green, or orange fluorescent colors. Although not originally developed for the ornamental fish trade, it is the first genetically modified animal to become publicly available as a pet.