Transgenic DNA introgressed into traditional maize landraces in Oaxaca, Mexico

Concerns have been raised about the potential effects of transgenic introdu ctions on the genetic diversity of crop landraces and wild relatives in are as of crop origin and diversification, as this diversity is considered esse ntial for global food security. Direct effects on non-target species(1,2), and the possibility of unintentionally transferring traits of ecological re levance onto landraces and wild relatives have also been sources of concern (3,4). The degree of genetic connectivity between industrial crops and thei r progenitors in landraces and wild relatives is a principal determinant of the evolutionary history of crops and agroecosystems throughout the world( 5,6). Recent introductions of transgenic DNA constructs into agricultural f ields provide unique markers to measure such connectivity. For these reason s, the detection of transgenic DNA in crop landraces is of critical importa nce. Here we report the presence of introgressed transgenic DNA constructs in native maize landraces grown in remote mountains in Oaxaca, Mexico, part of the Mesoamerican centre of origin and diversification of this crop(7-9) .