Print PageThe numbers of transgenic crops, the types of transgenes and the total acreage planted to transgenic crops in the U.S. has been increasing since the introduction of the first transgenic crop in the early 1990s. In 2009, 93 % of the canola acreage in the U.S. or 6.4 million hectares was planted with herbicide resistant canola and 80 % of the papaya acreage was planted to transgenic ringspot virus resistant papaya. More recently, deregulation has been more difficult for some transgenic crops. For example, herbicide resistant alfalfa has been deregulated twice by the USDA, the first time in 2005 and the second time in 2011. A similar pattern is occurring with genetically modified sugar beets. The decision to deregulate a transgenic crop is based on Safety and requires an environmental impact statement for each crop and new transgene. I use transgenic squash and alfalfa as examples to illustrate how an evolutionary approach can be helpful to estimate some aspects of the environmental risk assessment process. In squash, I discuss factors that can influence the frequency of a transgene introgressing into wild squash populations. In alfalfa, I examine how insect pollinators move pollen around and ultimately spread the transgene.
Results/Conclusions
Gene flow is an evolutionary concept that is directly relevant to the risk of gene escape and the potential spread of transgenes between populations. Gene flow and selection help predict the frequency of a transgene in a population and the probability that a transgene gets established. Evolutionary research can help generate data needed by bio-regulators to assess the environmental risk of a particular transgene in a chosen crop. Transgenic crops is an area where evolution can contribute to policy decisions.
