|Cotton field. Picture by Aileen's Pics on Flickr|
Mexico is the centre of origin of domesticated cotton. Clearly, steps to protect wild cotton's natural diversification are critical for conservation and future breeding.
Despite this, GM cotton has been cultivated in the north of the country since 1996, and 21 gene transformation events have been approved there (5,985 permits to sow GM cotton were issued in the first 12 years).
Genes can escape through pollen and seeds. Because cotton plants are mainly self-pollinating and the two species grown commercially in the USA can't hybridise, there's little opportunity for gene movement through pollen. However, seeds have plenty of potential for dispersal: they survive much longer than pollen and can be moved far and wide by water, weather and birds; once the cotton fibre has been removed, the seeds end up as truckloads of animal feed (on their way into the human food-chain) travelling the highways.