ProdiGene Field Trials of Drug- and Chemical-Producing Corn
Information compiled from USDA’s website for field trials of genetically engineered crops (www.nbiap.vt.edu/cfdocs/fieldtests1.cfm)
An Excel file with a complete list of ProdiGene field trials nationwide is available upon request

Possible Substances :
Nebraska soybeans were contaminated with engineered corn grown by ProdiGene in 2001. All of the substances involved in these trials were kept secret as confidential business information (CBI), except one that listed the substances involved as aprotinin and gp120. ProdiGene has also reported that it is growing trypsin-corn on hundreds of acres in the Midwest, including Nebraska, though for some reason this trial is not listed on the USDA’s website. The ProdiGene permit for planting in Iowa in 2001 was simply listed as a pharmaceutical without further specification.

Aprotinin is a blood-clotting agent used to reduce blood loss in surgery. A version of aprotinin derived from cow lung tissue is sold by Bayer under the name of Trasylol. ProdiGene’s first reported field trial of corn genetically engineered to produce aprotinin was in Nebraska in 1998. ProdiGene sees several prospective uses for its corn-grown aprotinin: as a reagent in biological research, as a blood-clotting drug, and as a built-in insecticide similar to the Bt toxins in commercialized varieties of engineered corn. Aprotinin belongs to a class of substances known as trypsin inhibitors that are known to cause pancreatic disease when fed to animals. Aprotinin has insecticidal properties as well, and has been shown to shorten the lives of honeybees that ingest it at low levels. Expert scientific advisors to the EPA have recommended that transgenic plants producing trypsin inhibitors such as aprotinin be subjected to animal feeding experiments before approval:

“Like any transgenic plant with pesticide properties, those containing trypsin inhibitor should be tested for their biological effects at dietary concentrations which, at minimum, are likely to be encountered in the transgenic plant itself. Such studies should also be accompanied by tests designed to evaluate how much heat treatment may be necessary to reduce the trypsin inhibitor activity to non-toxic levels.”

It is not known if the government has required any animal testing on ProdiGene’s aprotinin-producing corn.

gp120 is a glycoprotein (protein with sugar groups attached) found on the surface of two strains of HIV and the closely related simian immunodeficiency virus (SIV). It is being grown in corn for possible development as an AIDS vaccine, though many researchers believe it will never be effective, and might even suppress an effective immune response in vaccinated individuals. Injection of gp120 into the brain of rats has been shown to kill brain cells, while injection into the human blood stream results in the death of white blood cells. It is not known if the USDA or FDA has conducted any environmental or health assessment of gp120-producing corn. It would seem advisable to test for possible adverse effects upon inhalation of or contact with gp120-corn dust and pollen.

Trypsin is a digestive enzyme used in biological research and pharmaceutical processing. It is traditionally obtained from cow or pig pancreas. ProdiGene announced plans to grow hundreds of acres of its trypsin-producing corn in the Midwest this year, including Nebraska, with hopes of marketing hundreds of pounds of corn-derived trypsin by year’s end. Trypsin is a known inhalant allergen, causing occupational asthma in pharmaceutical and industrial workers exposed to it. Similar concerns might apply to farmers and farmworkers exposed to trypsin-corn dust and pollen, especially since trypsin is produced at very high concentrations in corn kernels. Trypsin corn is reportedly being grown under the USDA’s weak “notification” system, which does not require a permit. A USDA spokesperson indicated that neither the USDA nor the FDA had conducted any health or environmental assessment of trypsin corn.

Another possible substance is laccase, an enzyme derived from a fungus. It is intended for use in the adhesives industry. ProdiGene foresees a market for corn-grown laccase that would require the planting of anywhere from 200,000 to 2 million acres of corn. A related version of laccase from the Japanese lacquer tree “may be harmful by inhalation, ingestion or skin absorption. Prolonged or repeated exposure may cause allergic reactions in certain sensitive individuals. The toxicological properties have not been thoroughly investigated.” Other biopharm crops reportedly grown by ProdiGene include experimental oral vaccines for hepatitis B and a pig disease, transmissible gastroenteritis. There is no indication that the USDA or the FDA has conducted any health or environmental assessment of these substances.

Endnotes:

1 Search on the following parameters: Phenotype category = Other; Institution = ProdiGene; Location = Nebraska.
2 For detailed treatments of the substances discussed below, including references, see “Manufacturing Drugs and Chemicals in Crops: Biopharming Poses New Threats to Consumers, Farmers, Food Companies and the Environment,” July 2002, by Bill Freese of Friends of the Earth for Genetically Engineered Food Alert. Available for downloading at www.foe.org/biopharm/.
3 “Mammalian Toxicity Assessment Guidelines for Protein Plant Pesticides,” Scientific Advisory Panel to the EPA, SAP Report No. 2000-03B, September 28, 2000.
4 Material Safety Data Sheet, Sigma Chemical Company website