George,

Why is it that no one was having a fit when we were doing this to fruit flies and bacteria, only when it is a cute bunny? Tagging genes with a visible reporter gene has been going on at least 20 years. I certainly have been doing it longer than I can remember. Here is how it works.

Generally speaking, if a critter, usually bacteria, yeast, nematodes or fruit flies, glows or changes colors it contains what is called a reporter gene. A gene that can be easily seen when it functions is replaced for the gene that you are studying. Its a lot easier to tell if a gene that turns yeast blue is working than trying to figure out if that gene is making an intermediate in the heme biosynthetic pathway. People do this in order to study how genes are regulated.

For instance, there are genes that when turned on at the incorrect time in an organisms life cause cancer. We would like to know how they normally function, how they function when they cause cancer, and have the drug companies created a drug that can adequately turn them off.

Alternatively how do genes that are regulated by oxygen change the levels that are expressed when there is a decrease in oxygen or an increase in alcohol? These reporter genes are generally meant for obtaining information that can later be used. These constructs are not used for gene therapy because the real gene is either gone, mostly gone or malformed.

When one wants to use the real gene for a product or gene therapy is when we must be very careful how these are designed. During the manipulations required to grow these genes in bacteria (which is where all cloned genes are propagated) the gene of choice can be altered. Companies and university workers go to great, sometimes contorted lengths to not change even one amino acid of the protein that the gene encodes. The danger is that even one amino acid change can cause our immune systems to see it as foreign instead of self, thus attacking the product that many thought would be therapeutic.

We have successfully been able to produce products that are safer than those that are naturally occuring. Because of the small size
and originally difficult means to eliminate HIV from blood products, many hemophiliacs receiving the blood factor to help with clotting and those who received vaccines for hepatitis were also innoculated with HIV. This danger has now been corrected by using cloned human products.

Now for the corn problem. Monsanto, Agrigenetics and many other crop oriented biotechnology firms have long been interested in altering corn proteins. As many vegetarians know, no single plant product can provide all the amino acids that a human is required to ingest. There are large parts of this planet where people cannot afford to eat meat.

In the interests of these billion people, many researchers have sought to make the protein in corn or rice a complete protein so that those who can only afford one source of food would receive a more complete nutrition. The problem with the taco corn is that during the manipulation of the gene some amino acids were changed that could possibly induce an immune response in some within the human population.

There are other versions of recombinant plants that do not cause a response, but due to our patent laws that company must make their product differently in order to market it. In order to add the 2 (if I remember correctly) missing amino acids, they must, by definition, change the amino acid content of that protein. One tries to design a protein, given our limited knowledge of our bodies, in a way that it would not be recognized as an invading organism. However, since this is not Star Trek: the Next Generation, it is often not known until trials whether or not the product would elicit a response.

In the case of this recombinant corn, the manufacturer opted to sell it only for livestock use and not for human consumption. It would definately not be in their best interests to feed humans something that could cause a response. I can only assume that somewhere between the manufacturer and the taco someone misrepresented the product. Its probably cheaper to buy feed corn than FDA approved corn.

Now for green bunnies. Classically, reporter genes were studied in bacteria and yeast because their generation times can be measured in minutes or hours and researchers want to know the answer as quickly as possible. However, the better a gene is understood and the closer it gets to being used in human therapy, the more likely it is that this gene will have to be studied in an organism a little closer in evolution to humans. Bunnies, being mammals, are a lot closer than yeast.

If we ever want to cure some of the horrible genetic defects in the human population, people will have to become accustomed to green and blue cute fuzzy things. It is not moral, ethical or legal to do this to humans until it has been determined that all possible risks have been eliminated.

Of course the researcher would deny that he made Alba for artistic reasons. If it were in this country it would definately mean the removal of his license to use recombinant DNA, ability to use animal models, and probably all of his government grants--present and future. This is serious stuff to claim that it is for art. No detraction to art intended. It is difficult enough to justify the use of animals for research, let alone entertainment.

I personally have turned down jobs working on other primates because the conditions so freaked me out. Only to discover later that the person in Philadelphia interviewing me was arrested for extreme cruelty to the monkeys. Its people like him that make obtaining a Rhesus monkey for even low impact research almost impossible.

Ellora Young (electronic mail, October 20, 2000).