Not dangerous, just morally ambiguous.
Not dangerous, just morally ambiguous.

One of the more popular exhibits at The Tech Museum of Innovation in San Jose is the wetlab. This is where museum visitors get to add the green fluorescent protein (GFP) gene from jellyfish to bacteria to get the bacteria to glow green. The 20,000 or so people who do this each year get to learn about how genetically engineering bacteria can help to create important medicines like EPO, insulin and growth hormone.

The exhibit is getting a little long in the tooth so I was looking for ways to give it a bit of a refresh. One idea we’re thinking about is adding some new colors to the mix. We might give visitors the option of using a gene from coral that makes the bacteria glow red or a mutant version of GFP that glows blue in addition to the current green one. We may even add a station that lets visitors paint living pictures using these different colored bacteria.

Another simple but fun refresh I wanted to add was an aquarium full of GloFish. These are fish that have had various fluorescent genes inserted into their DNA so they glow incredibly brightly. I thought this was an easy and visually fun way to get into a discussion about how GFP has become such a powerful tool for scientists. I was only half right.

Getting GloFish into an exhibit here in California is nontrivial because they are illegal. That’s right: they are legal in the other 49 states but illegal here. I need to get a special permit from the California Department of Fish and Wildlife to have GloFish merrily swimming at The Tech. And Sheldon (from The Big Bang Theory) would have been breaking California law by having them in his Pasadena apartment in the episode, “The Luminous Fish Effect.”

Wouldn't this look spiffy with a bunch of GloFish swimming in a tank?
Wouldn’t this look spiffy with a bunch of GloFish swimming in a tank?

Now they aren’t illegal because they are dangerous. They won’t spread disease, take over native fishes or swallow swimmers whole. They are small, tropical fish that won’t survive long in California’s chilly waters. And the few that do manage to survive are twice as likely to be eaten by predatory fish compared to their non-glowing brethren. This means that because of natural selection they would quickly be wiped out.

If they aren’t dangerous, why in the world are they illegal? Because the Fish and Game Commission decided back in 2003 that GloFish were the result of a trivial use for a powerful technology. They felt that these fish should not have been made and therefore Californians should not be able to have them. The commission imposed their set of values on the rest of us.

This is even though these fish are really a spinoff of a more useful technology. Scientists in Singapore created GloFish as part of a process of creating living pollution sensors. The idea was that the fish would only glow when pollutants are around and so they could serve as an early indicator of pollution. In one sense, then, GloFish are really more like Teflon or Tang—useful byproducts of more productive research.

The banning of GloFish is probably too trivial an issue to stir up enough protest to get it reversed. So if I decide to go ahead, I’ll apply for the permit. Maybe then at least some people in California will be able to see these cool fish in person.

Newest GloFish May Be More Worrisome

Lighten Up, California: Why GloFish Can’t Glow in the Golden State 15 February,2013Dr. Barry Starr
  • Wes

    I think that the author of this post does not fully appreciate the concerns that so many have over GMO’s. While every detail that he wrote might be true concerning restricted use of GloFish, and given that introducing a vitamin A producing gene into “yellow rice” has great benefit, the overall concern is that the genetic modification do not remain isolated. Consider a vegetable used to produce insulin. While this sounds good, having that gene spread through natural means could have devastating health results for some. Consider that Roundup Ready genes from Monsanto have been documented as having spread as far as 15 miles from test plots in Oregon grass farm. Once released, there are no longer any controls at all.

    • Barry

      I’ve argued in the past that we need to take a close look at each GM food and determine if the risks outweigh the benefits (see my previous blog at for instance). In other words, I am arguing against a knee jerk reaction that opposes all GM foods no matter how low their risk is or how great their benefit. GloFish pose no risk whatsoever and golden rice have a very low risk and a very high reward and so I support the use of each. Insulin in veggies I am not so sure of (although I am obviously totally supportive of insulin in bacteria in a factory setting) and I can see why some people might be opposed to RoundUp Ready crops.

      • John Fiorentino

        Bravo!! Barry.

        • Raquel Santiago

          This article is no longer correct. Glofish are now allowed in California. Amendments being filed to allow them. They are now for sale.

      • John Fiorentino

        I think the following article about a recent study in the respected Journal
        SCIENCE points to some of the reasons many people have
        questions and reservations about GMO’s.

        Even though the study concerns trace amounts of Pharmaceuticals in
        drinking water, I think it amply demonstrates the fragility of the eco
        system and the fact that we probably THINK we know
        more about these things than we actually do.

        I also think it noteworthy to recognize that the fish in the below study
        were affected by a concentration of only 2 parts per BILLION of
        the anti-anxiety drug oxazepam

        Study: Fish in drug-tainted water suffer reaction
        By JEFF DONN |
        Associated Press – 23 hrs ago

        BOSTON (AP) — What happens to fish that swim in waters tainted by traces of
        drugs that people take? When it’s an anti-anxiety drug, they become hyper,
        anti-social and aggressive, a study found. They even get the munchies.

        It may sound funny, but it could threaten the fish population and upset the
        delicate dynamics of the marine environment, scientists say.

        The findings, published online Thursday in the journal Science, add to the
        mounting evidence that minuscule amounts of medicines in rivers and streams can
        alter the biology and behavior of fish and other marine animals.

        “I think people are starting to understand that pharmaceuticals are
        environmental contaminants,” said Dana Kolpin, a researcher for the U.S.
        Geological Survey who is familiar with the study.

        Calling their results alarming, the Swedish researchers who did the study
        suspect the little drugged fish could become easier targets for bigger fish
        because they are more likely to venture alone into unfamiliar places.

        “We know that in a predator-prey relation, increased boldness and activity
        combined with decreased sociality … means you’re going to be somebody’s lunch
        quite soon,” said Gregory Moller, a toxicologist at the University of Idaho and
        Washington State University. “It removes the natural balance.”

        Researchers around the world have been taking a close look at the effects of
        pharmaceuticals in extremely low concentrations, measured in parts per billion.
        Such drugs have turned up in waterways in Europe, the U.S. and elsewhere over
        the past decade.

        They come mostly from humans and farm animals; the drugs pass through their
        bodies in unmetabolized form. These drug traces are then piped to water
        treatment plants, which are not designed to remove them from the cleaned water
        that flows back into streams and rivers.

        The Associated Press first reported in 2008 that the drinking water of at
        least 51 million Americans carries low concentrations of many common drugs. The
        findings were based on questionnaires sent to water utilities, which reported
        the presence of antibiotics, sedatives, sex hormones and other drugs.

        The news reports led to congressional hearings and legislation, more water
        testing and more public disclosure. To this day, though, there are no mandatory
        U.S. limits on pharmaceuticals in waterways.

        The research team at Sweden’s Umea University used minute concentrations of 2
        parts per billion of the anti-anxiety drug oxazepam, similar to concentrations
        found in real waters. The drug belongs to a widely used class of medicines known
        as benzodiazepines that includes Valium and Librium.

        The team put young wild European perch into an aquarium, exposed them to
        these highly diluted drugs and then carefully measured feeding, schooling,
        movement and hiding behavior. They found that drug-exposed fish moved more, fed
        more aggressively, hid less and tended to school less than unexposed fish. On
        average, the drugged fish were more than twice as active as the others,
        researcher Micael Jonsson said. The effects were more pronounced at higher drug

        “Our first thought is, this is like a person diagnosed with ADHD,” said
        Jonsson, referring to attention deficit-hyperactivity disorder. “They become
        asocial and more active than they should be.”

        Tomas Brodin, another member of the research team, called the drug’s
        environmental impact a global problem. “We find these concentrations or close to
        them all over the world, and it’s quite possible or even probable that these
        behavioral effects are taking place as we speak,” he said Thursday in Boston at
        the annual meeting of the American Association for the Advancement of

        Most previous research on trace drugs and marine life has focused on
        biological changes, such as male fish that take on female characteristics.
        However, a 2009 study found that tiny concentrations of antidepressants made
        fathead minnows more vulnerable to predators.

        It is not clear exactly how long-term drug exposure, beyond the seven days in
        this study, would affect real fish in real rivers and streams. The Swedish
        researchers argue that the drug-induced changes could jeopardize populations of
        this sport and commercial fish, which lives in both fresh and brackish

        Water toxins specialist Anne McElroy of Stony Brook University in New York
        agreed: “These lower chronic exposures that may alter things like animals’
        mating behavior or its ability to catch food or its ability to avoid being eaten
        — over time, that could really affect a population.”

        Another possibility, the researchers said, is that more aggressive feeding by
        the perch on zooplankton could reduce the numbers of these tiny creatures. Since
        zooplankton feed on algae, a drop in their numbers could allow algae to grow
        unchecked. That, in turn, could choke other marine life.

        The Swedish team said it is highly unlikely people would be harmed by eating
        such drug-exposed fish. Jonsson said a person would have to eat 4 tons of perch
        to consume the equivalent of a single pill.

        Researchers said more work is needed to develop better ways of removing drugs
        from water at treatment plants. They also said unused drugs should be brought to
        take-back programs where they exist, instead of being flushed down the toilet.
        And they called on pharmaceutical companies to work on “greener” drugs that
        degrade more easily.

        Sandoz, one of three companies approved to sell oxazepam in the U.S., “shares
        society’s desire to protect the environment and takes steps to minimize the
        environmental impact of its products over their life cycle,” spokeswoman Julie
        Masow said in an emailed statement. She provided no details.


        Overview of the drug:


    • Vm

      is there any proof that the spread of the roundup ready genes or the spread of the glowing fish genes has caused any harm?

  • BDK

    How’s the permit process going?

  • Pingback: GloFish Information | Aquatic Mag()

  • Well doing research on glofish fish profile – I stumbled onto this article and actually never knew about glofish being ban from California. Go figure, it would be California out of all the states in the US to do it though haha. Definitely made me aware and I hope to pass it on to all my viewers that might get glofish for their aquarium.

  • Windy Page

    All so true. If they see this as logical banning a “man made tropical fish”. Then almost all tropical fish these days would be banned also. Back in the day when a aquarium enthusiast would want salt water fish, their only option was to buy wild caught, cyanide, dynamited left overs from our disappearing oceans. Now.. In today’s market there thousands of new designer species of fish, corals and invertabreas that just do not and could not exist in the wild. They justifiably cost a fortune, but to me, buying a fish that was farmed instead of cruely harvested sounds great! I’ve been raising fish my whole life, and owning a pet store along the way. The whole Gmo thing.. Has nothing to do with keeping a pet. Might as well ban cocker spaniels because again like all dogs, cats, horses and rodents are man made.


Dr. Barry Starr

Dr. Barry Starr (@geneticsboy) is a Geneticist-in-Residence at The Tech Museum of Innovation in San Jose, CA and runs their Stanford at The Tech program. The program is part of an ongoing collaboration between the Stanford Department of Genetics and The Tech Museum of Innovation. Together these two partners created the Genetics: Technology with a Twist exhibition.

You can also see additional posts by Barry at KQED Science, and read his previous contributions to QUEST, a project dedicated to exploring the Science of Sustainability.

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