2/9/2013 7:00 AM
By Miles Jackson New Jersey Correspondent
ATLANTIC CITY, N.J. — Farmers have been genetically modifying crops through selective breeding since the dawn of agriculture, but the speed and accuracy of such modifications has increased greatly by the use of genetic engineering.
And while traditional genetic modification was limited to breeding crops of the same species, genetic engineering has enabled scientists to pass on traits to a crop from completely different species.
At a workshop during this week’s Agricultural Convention and Trade Show at the Trump Taj Mahal in Atlantic City, speakers talked about the methods by which crops are genetically engineered, possible problems and benefits from such engineering, and public perception of food products that meet the definition of containing GMOs, or genetically modified organisms.
Although the European Union and some other nations have banned growing or importing genetically engineered, or GE, crops, the speakers said there is no evidence that such crops pose any danger to the humans or animals that consume them.
“Current (GE) crops grown in the United States are safe to eat,” said Greg Jaffe, director of the Project on Biotechnology for the Center for Science in the Public Interest, a nonprofit organization based in Washington. “GE crops have been grown and consumed in America since 1996 with no apparent ill effects, including allergic reactions.”
The crops grown using GE are canola, corn, cotton, soybeans and sugar beets, Jaffe said. Most of these crops are engineered to be tolerant of wide-specturm herbicides such as Roundup or contain proteins of bacillus thuringiensis (Bt), a soil-borne bacteria that kills certain crop pests but is harmless when ingested by humans, Jaffe said.
Most GE crops are refined into additives for processed foods, such as sugar or oils, at which time the genetically engineered DNA is removed, making them identical to oils and sugar made from non-GE crops, he said.
Work is being done to create crops that contain more protein or higher levels of Omega-3 fats that are beneficial to humans, but current GE crops mostly produce “benefits for the farmers and the environment, not necessarily the consumer,” he said.
But Jaffe also warned that there is no monitoring of consumption of GE crops to detect adverse effects, such as food allergies, which could go undetected or be attributed to some other cause.
Although the U.S. Environmental Protection Agency and USDA currently do have some regulations for GE crops, Jaffe said, there are loopholes in them.
The federal FDA currently regulates GE animal species as it would any medicine for use in animals. Although no application for a GE animal species for human consumption has yet been approved, the agency is expected to approve AquaAdvantage, a species of rapid-growing salmon in the near future, he said.
There are no requirements for labeling food products containing GMOs, Jaffe said, although some food is labeled as “not containing GMOs.”
The benefits genetic engineering provides plant breeders is the speed in which certain traits can be conferred on commercial crops as well as the ability to transfer traits to other species, said Stacey Bonos, professor of plant breeding at Rutgers University.
It can take decades of selective breeding to transfer a certain trait from one variety of plant to another, a process done incrementally through many generations, she said. But splicing a certain section of DNA that confers herbicide resistance or other desirable traits into a commercial plant variety can be done in a much shorter period of time.
Transferring a single gene from one species into another, for instance, has allowed plant breeders to create corn varieties that kill corn rootworms by transferring a gene with the Bt protein toxic to worms into the target corn variety, she said.
While the benefits of GE crops are obvious, so are the potential pitfalls of the practice, Jaffe said.
Although Roundup Ready crops have allowed farmers to use fewer herbicides, he said, and crops with disease and pest resistance have cut down on pesticides, natural crossbreeding of Roundup resistant commercial crops with wild weeds has created new generations of weeds that are now resistant to the herbicide.
Resistance to Roundup has been detected in 10 weed species in 22 states, something that is expected to become a bigger problem as use of Roundup Ready crops grows from the 150 million acres of such crops planted in the United States in 2012, Jaffe said
And while pests targeted by Bt corn and cotton have not, as of yet, developed a resistance to the GE plant varieties, such resistance most likely will develop in the future, he said, especially if farmers use the GE crops in place of such conventional growing practices as crop rotation
Also a problem is the failure of farmers to grow blocks of non-Bt crops as a refuge for pests that are not resistant to Bt pesticides although the U.S. Environmental Protection Agency imposed such an obligation on farmers who planted Bt corn and cotton.
“Compliance has gone down while adoption of growing Bt crops has gone up,” Jaffe said, and noncomplience “could lead to insect pests developing resistance to Bt crops and Bt (microbial) insecticides.”
“The key point is that growing genetically engineered crops as it is being done now is not sustainable,” he said.
Some plant breeders are banking on the development of crops resistant to other herbicides such as 2-4 D, which is already in process, Jaffe said. But while the “stacking of HT (herbicide tolerant) crops will work in the short term, it will not work in the long term.”
A panel of farmers, scientists and public interest groups, called the Advisory Committee on Biotechnology and 21st Century Agriculture, (AC21) recently submitted a report on GE crops to the USDA that recommended steps to foster co-existence among the nation’s diverse agricultural base built on conventional, organic and genetically engineered crops, said Jaffe, who was a member of the committee.
The committee came up with five recommendations that “would allow farmers to make their own choices about what to do with their land and foster coexistence between farmers growing different types of crops,” according to the report.
The most controversial recommendation was one suggesting the creation an insurance-based compensation mechanism that would pay for possible economic losses from contamination of organic crops with GE crops or even conventional crops, according to the report.
Other recommendations included funding an educational and outreach initiative on co-existence between farmers of GE, conventional and organic crops, funding research relevant to such co-existence and working with seed suppliers to ensure a diverse and high quality commercial seed supply.
“There has to be some mechanism to prompt seed quality, not just GE seed quality,” Jaffe said. “Public seed banks are not going to be able to do the job. We need to have good, robust non-GE seed varieties.”
Although GE foods are safe, Jaffe said each method of genetic engineering of each variety must be taken on a case-by-case basis and steps should be taken to allow farmers and consumers to make decisions on whether they grow or consume GE foods products.