The Evolutionary Consequences of Gmo Escape
The Evolutionary Consequences of GMO Escape Hybridization between genetically modified plants and populations of crop plants is a major hazard to be avoided in conducting field trials of genetically modified plants. The reason to avoid this is that gene flow from the transgenic plants into the crop population results in the creation of unwanted and potentially devastating hybrids. This essay explores some of the mechanisms behind gene flow between species, and their evolutionary consequences. The main mechanism for gene flow between species is a hybrid population, either able to reproduce with parental species and thus forming a bridge for gene flow, or reproductively isolated from the parental species and undergoing hybrid speciation to form a new species. Research in this area seems to indicate that the crops most at risk of significant transgenic invasion are those with a fixed genetic load, thus the best preventative measure would be to increase genetic variability in crop populations.
Introduction
What if? It’s the question that everyone is asking. What if the stock market collapses completely? What if we have to sell our house? What if Transgenic Organisms escape and initiate gene flow between themselves and a population of crop plants? Well, perhaps the latter is not on quite everyone’s lips, but it is the question which this essay sets out to address. The regulations set out by the New Zealand Environmental Risk Management Authority regarding field trials with transgenic plants are there for a reason; gene flow between transgenic plants and crop plant populations is a very real possibility. It occurs mainly via the creation of hybrids between the species. These hybrids may then act as a sort of genetic bridge for gene flow from one species to the other, or they may be reproductively isolated from both of the parental species and become a new species through hybrid speciation. Whether the genetic recombination occurs via a hybrid genetic
Introduction
What if? It’s the question that everyone is asking. What if the stock market collapses completely? What if we have to sell our house? What if Transgenic Organisms escape and initiate gene flow between themselves and a population of crop plants? Well, perhaps the latter is not on quite everyone’s lips, but it is the question which this essay sets out to address. The regulations set out by the New Zealand Environmental Risk Management Authority regarding field trials with transgenic plants are there for a reason; gene flow between transgenic plants and crop plant populations is a very real possibility. It occurs mainly via the creation of hybrids between the species. These hybrids may then act as a sort of genetic bridge for gene flow from one species to the other, or they may be reproductively isolated from both of the parental species and become a new species through hybrid speciation. Whether the genetic recombination occurs via a hybrid genetic
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