Transgenic DNA introgressed into traditional maize landraces in Oaxaca, Mexico

  • Nature volume 414, pages 541543 (29 November 2001)
  • doi:10.1038/35107068
  • Download Citation


Concerns have been raised about the potential effects of transgenic introductions on the genetic diversity of crop landraces and wild relatives in areas of crop origin and diversification, as this diversity is considered essential for global food security. Direct effects on non-target species1,2, and the possibility of unintentionally transferring traits of ecological relevance onto landraces and wild relatives have also been sources of concern3,4. The degree of genetic connectivity between industrial crops and their progenitors in landraces and wild relatives is a principal determinant of the evolutionary history of crops and agroecosystems throughout the world5,6. Recent introductions of transgenic DNA constructs into agricultural fields provide unique markers to measure such connectivity. For these reasons, the detection of transgenic DNA in crop landraces is of critical importance. 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 crop7,8,9.

  • Subscribe to Nature for full access:



Additional access options:

Already a subscriber?  Log in  now or  Register  for online access.


  1. 1.

    , & Transgenic pollen harms monarch larvae. Nature 399, 214 (1999).

  2. 2.

    , & Insecticidal toxin in root exudates from Bt corn. Nature 402, 480 (1999).

  3. 3.

    When transgenes wander, should we worry? Plant Physiol. 125, 1543–1545 (2001).

  4. 4.

    Molecular evidence for gene flow among Zea species—genes transformed into maize through genetic engineering could be transferred to its wild relatives, the Teosintes. Bioscience 40, 443–448 (1990).

  5. 5.

    , & Gene flow and introgression from domesticated plants into their wild relatives. Annu. Rev. Ecol. Syst. 30, 539–563 (1999).

  6. 6.

    & Of genes and genomes and the origin of maize. Trends Genet. 14, 327–332 (1998).

  7. 7.

    , , , & The limits of selection during maize domestication. Nature 398, 236–239 (1999).

  8. 8.

    & The earliest archaeological maize (Zea mays L.) from highland Mexico: new accelerator mass spectrometry dates and their implications. Proc. Natl Acad. Sci. USA 98, 2101–2103 (2001).

  9. 9.

    From teosinte to maize: the catastrophic sexual transmutation. Science 222, 886–894 (1983).

  10. 10.

    et al. A method of detecting recombinant DNAs from four lines of genetically modified maize. Shokuhin Eiseigaku Zasshi 41, 137–143 (2000).

  11. 11.

    , , & Detection of genetically modified organisms (GMOs) by PCR: a brief review of methodologies available. Trends Food Sci. Technol. 9, 380–388 (1999).

  12. 12.

    Development of Methods to Identify Foods Produced by Means of Genetic Engineering EU Project SMT4-CT96-2072 (Bundesinstitut für gesundheitlichen Verbraucherschutz und Veterinärmedizin, Berlin, 1999).

  13. 13.

    & Transgenic DNA integrated into the oat genome is frequently interspersed by host DNA. Proc. Natl Acad. Sci. USA 95, 12106–12110 (1998).

  14. 14.

    & in Methods in Molecular Biology (ed. Harwood, A.) 293–301 (Humana, Totowa, New Jersey, 1996).

  15. 15.

    , & Event specific transgene detection in Bt11 corn by quantitative PCR at the integration site. Lebensm.-Wiss. Technol. 33, 210–216 (2000).

Download references


We thank the Union de Comunidades Zapoteco Chinanteca (UZACHI) for access to their field laboratory, Y. Lara (Estudios Rurales y Asesoría, Oaxaca) for facilitation, A. King for Peruvian maize samples and CIMMYT maize germplasm bank for the historical control.

Author information


  1. Department of Environmental Science, Policy and Management, University of California, Berkeley, California 94720-3110, USA

    • David Quist
    •  & Ignacio H. Chapela


  1. Search for David Quist in:

  2. Search for Ignacio H. Chapela in:

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Ignacio H. Chapela.

Supplementary information


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.