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2-Plants: Mexican maize (3): Three scientific reports on maize GE contamination



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                                  PART I
-------------------------------- GENET-news --------------------------------

TITLE:  Transgenes in maize landraces in Oaxaca: Official report on the
        extent and implications
SOURCE: 7th International Symposium on The Biosafety of Genetically
        Modified Organisms, by Ariel Alvarez-Morales
        http://www.worldbiosafety.net/title%20paper.htm
DATE:   Oct 2002

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Transgenes in maize landraces in Oaxaca: Official report on the extent and 
implications

Ariel Alvarez-Morales

Department of Plant Genetic Engineering, Center for Research and Advanced 
Studies (CINVESTAV-IPN) Irapuato Unit.

In November 2001 a report was published indicating that transgenes had been 
found in landraces of corn grown in the sierra of Oaxaca, Mexico (Quist, D. 
& Chapela, I.H., 2001 Nature 414:541-543). This report initiated a long 
debate on three main subjects: 1) The technical qualification of the 
report; 2) The validity of the results presented and 3) The possible 
consequences and implications that such an event could have.

As a consequence of such report the Mexican Government initiated a 
preliminary sampling and analysis through the National Institute of Ecology 
which indicated the presence of transgenes in corn in two states. Based on 
these findings, the Secretary of Agriculture, requested an investigation 
into the subject. An "ad hocÓ committee was formed which included experts 
from different areas of expertise. The first step was to devise an approach 
to obtain representative samples from the State of Oaxaca and the 
neighboring State of Puebla. Once the sampling strategy had been planned it 
had to be implemented ensuring the "chain of custodyÓ and that all relevant 
information was obtained for each sample at each location. The samples 
where then processed and distributed to the institutions that were going to 
carry out the testing. Tests performed on the samples included PCR for 
general transgenic traits such as the 35S promoter, NOS terminator or cry 
genes; protein analysis using "strip testsÓ and ELISAs for specific 
proteins such as PAT, CP4, Cry1A and Cry9C; sequence and Southern blot 
analysis to confirm the findings and identity of some of the genes found.

Up to this moment, the results presented by the Mexican Government have 
shown that transgenes such as cry1A can be found extensively in land races 
throughout the State of Oaxaca. The presence of cry9C has not been detected 
in any of the samples tested. As for any apparent consequences to the 
landraces themselves, this so far has not been the case. The small growers 
have not reported any phenotypic changes in their crops that could suggest 
that a major modification could take place. The changes observed are those 
expected when the farmers use a hybrid to "enhanceÓ or improve their 
landraces, a practice that is very common among small growers in this area.


                                  PART II
-------------------------------- GENET-news --------------------------------

TITLE:  Global and multidisciplinary approach to study the feasibility of
        introducing transgenic landraces of maize in Mexico aimed to help
        small rural communities
SOURCE: 7th International Symposium on The Biosafety of Genetically
        Modified Organisms, by Alba E. Jofre-Garfias & Ariel Alvarez-Morales
        http://www.worldbiosafety.net/title%20paper.htm
DATE:   Oct 2002

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Global and multidisciplinary approach to study the feasibility of 
introducing transgenic landraces of maize in Mexico aimed to help small 
rural communities.

Alba E. Jofre-Garfias and Ariel Alvarez-Morales

Department of Plant Genetic Engineering, Center for Research and Advanced 
Studies (CINVESTAV-IPN) Irapuato Unit.

One of the most widely claimed benefits of agricultural biotechnology has 
been its potential to substantially contribute to alleviate the problems of 
hunger and poverty in developing countries. In the case of Mexico, maize 
has always been recognized as a staple crop and its main role in the diet 
of the Mexican people is evident. However, maize is also extremely 
important in Mexican tradition and folklore. It has been suggested that the 
introduction of high-yielding maize, whether hybrids or transgenic, may 
displace the local varieties and landraces which are normally less 
productive, thus leading not only to loose valuable sources of germplasm, 
but also to the lose of tradition and cultural identity.

Mexico adopted a de facto moratorium to any release of transgenic maize 
with the idea of first obtaining reliable information on the possible 
effects of the release of these materials on biodiversity as a whole, on 
teosinte in particular, and at the social and economic level. Because open 
pollination is the common behavior in maize varieties and more than 80% of 
our farmers keep seed for planting year after year, the possibility exists 
for gene flow to wild relatives and landraces with a potential impact on 
the use and sustainable conservation of biodiversity in the specific area 
of the release. The potential problems in each region depend on the 
particular socioeconomic and environmental conditions that prevail, as well 
as the scale of use. Thus, two types of concerns can readily be identified, 
those directly involving teosinte and maize biodiversity, and those related 
to changing the habits or impoverishing even more the rural populations 
that traditionally grow the landraces.

The purpose of this project is precisely to obtain preliminary data without 
the use of transgenic materials, in order to be in a position to develop 
science-based environmental risk assessments and risk-benefit evaluations. 
The approach involves the simultaneous evaluation of Social, Biodiversity 
and Biotechnology Issues through the concerted efforts of social 
scientists, ecologists, environmental scientists and biotechnologists from 
different institutions working together with selected rural communities who 
will play a prominent role in the development of this project as well as in 
deciding whether or not transgenic maize may help them to improve their way 
of life.


                                  PART III
-------------------------------- GENET-news --------------------------------

TITLE:  Concerns about the effect of transgene introgression in maize
        landraces and teosinte
SOURCE: 7th International Symposium on The Biosafety of Genetically
        Modified Organisms, by Jose de Jesus Sanchez-Gonzalez
        http://www.worldbiosafety.net/title%20paper.htm
DATE:   Oct 2002

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Concerns about the effect of transgene introgression in maize landraces and 
teosinte

Jose de Jesus Sanchez-Gonzalez 1
1 Centro Universitario de Ciencias Biologicas y Agropecuarias, Universidad 
de Guadalajara, Mexico

Mesoamerica is a region where plant domestication occurred about 10,000 
years ago. Most scientists currently agree that maize was domesticated in 
Mexico and descended from an annual species of teosinte (Zea mays ssp. 
parviglumis). Costs and benefits of transgenic crops for Mexican 
agriculture have been the subject in several forums for the past ten years. 
Today, an intense debate continues, and this issue has been raised 
questions about the extent of the knowledge available about the long-term 
effects of this technology on biodiversity in centers of origin of 
cultivated plants, already threatened by habitat alteration. This paper 
presents data related to the importance of Zea species in Mexico and 
information about ongoing research that may help to conduct a scientific 
risk assessment for transgenic maize technology adoption. Great advances 
have been made in knowledge of the natural distribution of teosinte in 
Mexico, more gene-flow studies between maize and teosinte have been 
completed and more knowledge about genetic diversity, genetic 
incompatibility systems, and about insects that affect teosinte and maize 
are available. The most important concerns that have influenced the debate 
about the eventual release of transgenic maize in Mexico have been 
questions about the potential of transgenic maize to modify genetic 
diversity of landraces and their quality as food. Another set of concerns 
is related to the risks associated to transgene escape and its dispersal 
into teosinte species and potentially enhancing their ability to survive or 
compete with another species. As a result of several national and 
international conferences, consensus exists indicating that current 
knowledge in Mexico is insufficient for assessing risks and benefits of 
transgenic maize. It is critical to develop a system for risk assessment 
within the context of current practices and threats to understand the 
impact, if any, from modern varieties (conventional and transgenic) on 
genetic diversity of landraces and teosinte. 



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