Keeping Tabs on the Next Generation of Transgenic Crops

 
'Scientists Develop Framework to monitor second-generation transgenic crops'

MADISON, WI, – A team of government and university crop scientists from across Canada has developed a scientific framework for monitoring the release of second-generation genetically modified crops. The framework is designed to assess the risks of novel genes entering wild populations.

First-generation genetically modified (GM)/transgenic crops with novel traits have been grown in a number of countries since the 1990’s. Most of these crops had a single gene that allowed them to tolerate herbicide application, giving them an advantage over wild species.
 
Second-generation transgenic crops are now being tested in confined field trials around the world. Some of these traits will allow crops to tolerate environmental stress such as drought, cold, salt, heat, or flood. Other traits being developed may lead to increased yield or lower nutrient requirements, or increase tolerance to disease and pathogens.
 
With novel traits from first-generation transgenic crops now being discovered in the wild, notably in wild canola in Canada and the U.S., accurately estimating the environmental impact of these new crops is becoming increasingly important.
 
The team of scientists - Hugh Beckie, Linda Hall, Marie-Josée Simard, Julia Leeson, and Christian Willenborg – used drought tolerant canola as a model crop to develop their post release monitoring protocol. The review and interpretation article was published in the September-October 2010 edition of Crop Science, a publication of the Crop Science Society of America.
 
Before crops with new traits can be released, the developer must conduct an environmental risk assessment on the crop. According to the authors, these trials are generally too small to uncover the uncertainties inherent in the second-generation crops before they are released. The post monitoring procedure the research team developed is designed to provide additional risk management.
 
Concrete steps are outlined for each of the four phases of the framework – (1) defining the problem; (2) project management and monitoring procedure; (3) implementation; and (4) regulatory decision.
 
Using drought-tolerant canola as a case specific-example of how to use the framework, the researchers identified several potential environmental risks associated with cultivation of this crop. The primary concern was increased of invasiveness wild, self-perpetuating populations, and hybridizations between transgenic crops and weedy relatives. Also identified was backcrossed progeny in non-cropped disturbed and natural areas next to transgenic fields, resulting in loss of abundance or biodiversity of native plant species.
 
One of the most important aspects of proper monitoring is the sampling design, specifically, appropriate site replication and sample size. The researchers detailed a statistical analysis to be able to detect effects of a specific magnitude.
 
The authors concluded that post release monitoring, through a comprehensive, pragmatic and science-based framework, can effectively address the greater uncertainties in the environmental risk assessment of these second-generation vs. first-generation transgenic crops and thereby enhance environmental protection and security of the food supply.

The full article is available for no charge for 30 days following the date of this summary. View the abstract at https://www.crops.org/publications/cs/abstracts/50/5/1587.