Genetically Modified Crops

3. Does conventional plant breeding have effects on health and the environment?

    The source document for this Digest states:

    Box 19
    Health and environmental concerns in conventional plant breeding
    Source: DANIDA, 2002
    Prior to the advent of genetic engineering, plant breeding was not subject to a great deal of regulation. Seed certification standards ensure the purity and quality of seeds, but little attention has been paid to the possible food safety or environmental impacts of new plant varieties derived from conventional breeding.

    Conventional plant breeding differs considerably from natural selection. Natural selection creates resilient biological systems; it ensures the development of an organism that contains properties that adapt it to a variety of environmental conditions and ensure continuation of the species. Artificial selection and conventional plant breeding break down precisely these resilient systems, thereby creating gene combinations that would rarely survive in nature.

    Conventional breeding has been responsible for a few cases of negative effects on human health. In one case a potato cultivar was found to contain excessive levels of naturally occurring toxins, and in another case a celery cultivar conventionally bred for high insect resistance caused a skin rash if harvested by hand without protection.

    Similarly, the potential impacts of conventionally bred crops on the environment or on farmers' traditional varieties generally have not given rise to regulatory controls, although some of the concerns associated with genetically transformed crops are equally applicable to conventional crops. Most of the world's major food crops are not native to their major production zones; rather, they originated in a few distinct “centres of origin” and were transferred to new production areas through migration and trade. Highly domesticated plants are grown all over the world and migration outside cultivated areas has only rarely caused a serious problem. Even when grown in their centre of origin, as with potatoes in South America or maize in Mexico, hybrids between cultivated and wild species have not been permanently established. There are several reports of gene flow between cultivated plants and their wild relatives but in general this has not been considered a problem.

    Source & ©: FAO "The State of Food and Agriculture 2003-2004"
    Chapter 5: Health and environmental impacts of transgenic crops , Box 19

    For details on: See FAO report:
    Bt cotton and reasons why it is grown (compared to conventional breeding) Chapter 4 , box 14
    Allergens and toxins (in gene technology and traditional breeding) Chapter 5 ,
    Section "Food safety implications", Subsection "Allergens and toxins"

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