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It is important for Colombia to put into question what strategies are being used to evaluate the current and future risk of the introduction of transgenic crops.

Genetically modified organisms (GMOs), or transgenic organisms, have a genetic composition that includes a new combination as the result of a controlled incorporation of genes belonging to alien species (transgenes). The development of genetically modified (GM) crops seeks to obtain greater yields, improve resistance against plagues, increase tolerance to herbicides, and lower production costs. Despite potential benefits, genetically modified crops may cause direct or indirect effects on the environment1,2such as flow of transgenes, creation of resistant weeds, and augmentation of pest resistances, among others. If these effects arise, they may only be determined in the long term.

Wild species are essential for the improvement of cultivated species and, consequently, for the sustainability of agriculture. However, GM crops in the Colombian territory increase the risk of transgenes being transferred to wild relatives, and an eventual expansion of these type of crops gives the possibility of their overlap with wild populations. Yet gene flow is not the major concern. The real problem lies in the nature of dispersed transgenes and the effects they may have in receptor species1, which include the loss of genetic diversity.

To understand and assuage the ecologic impacts of transgene flow, the following strategies must be developed:

• Determine the areas of real and potential distributions of species at risk with the aim of identifying overlapping with GM crops in the present and future.
• Develop studies of genetic diversity before introducing GM crops to determine species' genetic composition and variability.
• Construct a gene and seed bank with the goal of maintaining and fostering natural genetic variability, in addition to guaranteeing its future availability.
• Develop methodologies, with their respective monitoring programs, to detect transgenes in receptor species.