Glowfish Profile

GlowFish

The Science of GloFish®

Where do GloFish® fluorescent zebrafish come from?
GloFish® fluorescent zebrafish were originally bred to help detect environmental pollutants. By adding a natural fluorescence gene to the fish, scientists hoped to one day quickly and easily determine when a waterway is contaminated. The first step in developing a pollution-detecting fish was to create fish that would be fluorescent all the time. Scientists soon realized the public's interest in sharing the benefits of this research, a process which lead to GloFish® fluorescent fish.

How common is the use of fluorescent zebrafish in science?
For over a decade, fluorescent zebrafish have been relied upon by scientists worldwide to better understand important questions in genetics, molecular biology, and vertebrate development. Fluorescent zebrafish have been particularly helpful in understanding cellular disease and development, as well as cancer and gene therapy.

Where does the fluorescent color come from?
The fluorescent color in our fish is produced by a fluorescent protein gene, which creates the beautiful fluorescence that can be seen when looking at the fish. The fluorescent protein genes occur naturally, and are derived from marine organisms.

Do you have to add a fluorescence gene to every fish before it hatches?
No. Today's GloFish® fluorescent fish are bred from the offspring of fluorescent zebrafish that were originally developed several years ago. Each new GloFish® fluorescent fish inherits its unique color directly from its parents, maintains the color throughout its life, and passes the color along to its offspring.

How exactly do GloFish® fluorescent zebrafish help in the fight against pollution?
To achieve their goal of helping to fight water pollution, scientists are hoping to one day develop a ‘switch’ that will cause always-fluorescing zebrafish to selectively fluoresce in the presence of environmental toxins. A non-fluorescing fish will signal that the water is safe, while a fluorescing fish will signal trouble. To help further the research, a portion of the proceeds from sales of all GloFish® fluorescent fish goes directly to the lab where these fish were created. For more information on this project, please review the article entitled “Zebrafish as Pollution Indicators,” by the National University of Singapore.

What are the differences between fluorescent zebrafish and other zebrafish?
Aside from their brilliant color, fluorescent zebrafish are the same as other zebrafish. This includes everything from general care and temperature preferences to growth rate and life expectancy.

Does the fluorescence harm the fish?
No. The fish are as healthy as other zebrafish in every way. Scientists originally developed them several years ago by adding a natural fluorescence gene to the fish eggs before they hatched. Today's GloFish® fluorescent fish are bred from the offspring of these original fish.

Exactly how is the fluorescent protein gene added to the fish?
Every line of GloFish® fluorescent fish (i.e., GloFish® Starfire Red® Zebra, GloFish® Electric Green® Zebra, and GloFish® Sunburst Orange® Zebra) starts with a single fish. The general process of developing fluorescent fish, as illustrated in this chart, begins by adding a fluorescence gene to the fish before it hatches from its egg. Once the gene integrates into the genome (i.e., genetic code) of the embryo, the developing fish will be able to pass the fluorescence gene along to its offspring upon maturity. Because of this, the gene only needs to be added to one embryo; from that point forward, all subsequent fluorescent fish are the result of traditional breeding.

Are you going to create more fluorescent fish?
Scientists all around the world are working with fluorescent fish, whether it's to help protect the environment or come up with new disease-fighting drug therapies. As more fluorescent fish become available, they may be offered for sale to the public.

GloFish® and the Environment

Which federal agencies have reviewed these fish?
We have submitted detailed information regarding our fish to the U.S. Food & Drug Administration, which has jurisdiction over biotech animals, as they consider the added gene to be an “animal drug”. Consistent with the findings of scientists worldwide, the FDA, working in coordination with the United States Department of Agriculture and United States Fish & Wildlife Service, found no evidence that our fluorescent zebrafish pose any more threat to the environment than wild-type zebrafish. If you would like to read the FDA statement regarding our fish, please click here.

Have any other governmental agencies reviewed GloFish® fluorescent fish?
In addition to the Federal review described above, our fish have been reviewed by various state agencies, including the State of Florida Transgenic Aquatic Species Task Force and the California Department of Fish & Game. In accordance with the findings of the FDA, these reviews have concluded that our fluorescent zebrafish are as safe for the environment as wild-type zebrafish. To review their specific analyses, as well as those of independent third party experts, please see the GloFish® Science section of our website.

What will happen if a GloFish® fluorescent zebrafish escapes into the waterways?
Zebrafish are tropical fish and are unable to survive in non-tropical environments. They have been sold to aquarium owners worldwide for more than fifty years. Despite all these years of widespread distribution, zebrafish are only found in tropical environments, such as their native India. At the same time, please remember that GloFish® fluorescent fish are intended for use as aquarium fish only, and should never be intentionally released into the wild.

What if a GloFish® fluorescent zebrafish is eaten in the wild by another animal?
For an animal in the wild, eating a fluorescent zebrafish is the same as eating any other zebrafish. Their fluorescence is derived from a gene that is already found in nature and is completely safe for the environment. Just as eating a blue fish would not turn a predator blue, eating a fluorescent fish will not make a predator fluoresce.

Can humans eat GloFish®?
GloFish® fluorescent zebrafish, like all ornamental fish, are not intended for human consumption. Accordingly, GloFish should not be eaten.

How can buying GloFish® help in the fight against pollution?
Fluorescent zebrafish have already existed for several years and were originally developed to help fight pollution. By marketing these fish, we will allow people to have their own fluorescent fish while promoting the beneficial scientific goals behind their development. In fact, a portion of the proceeds from sales will go directly to the lab where these fish were created in order to further their research—research we hope will help to protect the environment and save lives.

Caring for GloFish®

Are GloFish® fluorescent zebrafish freshwater fish or saltwater fish?
Like any other zebrafish, GloFish® fluorescent zebrafish are freshwater fish. They should not be placed in a saltwater environment.

Where can I find detailed information about GloFish® fluorescent fish?
In general, guidelines for maintaining a happy and healthy GloFish® fluorescent fish can be found on our GloFish® Care page. Another great general resource for detailed care information about zebrafish is this website. Remember, our fish are cared for in the exact same way as non-fluorescent zebrafish, so this resource will directly apply to our fish.