Molecular strategies for gene containment in transgenic crops.
The potential of genetically modified (GM) crops to transfer foreign genes through pollen to related plant species has been cited as an environmental concern. Until more is known concerning the environmental impact of novel genes on indigenous crops and weeds, practical and regulatory considerations will likely require the adoption of gene-containment approaches for future generations of GM crops. Most molecular approaches with potential for controlling gene flow among crops and weeds have thus far focused on maternal inheritance, male sterility, and seed sterility. Several other containment strategies may also prove useful in restricting gene flow, including apomixis (vegetative propagation and asexual seed formation), cleistogamy (self-fertilization without opening of the flower), genome incompatibility, chemical induction/deletion of transgenes, fruit-specific excision of transgenes, and transgenic mitigation (transgenes that compromise fitness in the hybrid). As yet, however, no strategy has proved broadly applicable to all crop species, and a combination of approaches may prove most effective for engineering the next generation of GM crops.
Daniell
Henry
H
University of Central Florida, Department of Molecular Biology and Microbiology, 12722 Research Parkway, Orlando FL 32826-3227, USA. daniell@mail.ucf.edu
D018556:Crops, Agricultural / Q000187:drug effects; D017753:Ecosystem; D004787:Environmental Pollution / Q000517:prevention & control*; D018506:Gene Expression Regulation, Plant / Q000235:genetics*; D022761:Gene Transfer, Horizontal / Q000235:genetics*; D005818:Genetic Engineering / Q000379:methods*; D007246:Infertility / Q000235:genetics; D009154:Mutation / Q000235:genetics; D030821:Plants, Genetically Modified / Q000009:adverse effects / Q000235:genetics*; D012100:Reproduction, Asexual / Q000235:genetics; D012639:Seeds / Q000235:genetics