More Unknowns than Knowns with GM Crops

By Michelle Pressend · 24 Jul 2009

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Picture: Illuminating9_11
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Genetically modified (GMO) crops have more unknowns than knowns. Yet the South African government whole-heartily embraces this technology in the production of food crops, particularly maize, a staple food in South Africa.

The South African pro-GMO lobby is very proud of the fact that South Africa is the eighth biggest GMO producer in the world among the 13 largest biotechnology-producing countries. They also make claims that this technology is accepted worldwide, however many African countries have put a ban on GMO foods and in Europe, countries like Switzerland have put a moratorium on GMOs. 

The South African public was not part of the decision-making to adopt this technology in something that is as fundamental as food production and consumption.  It is only through the efforts of organisations such as Biowatch, the African Centre for Biosafety (ACB), South African Freeze Alliance on Genetic Engineering (SAFeAGE) and others that a critical awareness of the implications of GMOs has been created. 

Stephen Greenberg, rural development researcher and writer makes a relevant point on the introduction of new technology, "Before a new technology is introduced, it is necessary to ask whether it meets the requirements of greater choice and greater control over resources and production decisions by those who use the technology, and by those who will bear the consequences (positive or negative) of the use of that technology."

Evidence suggests that neither primary producers, in particular, poor producers such as small-scale farmers nor food consumers are likely to benefit from the introduction of GMO technology in agriculture either in the medium or long term. 

The impact of GMO technology on small-scale farmers is potentially devastating. GMO seeds only last for one season and farmers have to continually purchase seeds from the seed company. This not only creates dependency, but also locks farmers into long-term arrangements to purchase GMO seeds.

Many small-scale farmers save seeds and are involved in seed conservation methods to maintain indigenous and open pollinated varieties, which can be used over generations. So the purchasing of GMO seeds will not only create dependency, but also impact on cultural traditions practiced over years to maintain traditional and seed varieties. It has been documented that small-scale farmers have fallen into massive debt once they have started to purchase GM seeds

A number of 'knowledge gaps' are apparent in the implementation of this technology that the government, multinationals and agri-business must provide answers for. 

Firstly, speaking as someone with a Masters degree in science, having studied botany and biochemistry, the genetic central dogma of "one gene results in one protein" on which this technology is based, has advanced in the last ten or so years. 

In the post-genomic era, the transcription of DNA can make many different types of messenger RNA and many different proteins. Scientific studies have shown that the insertion of foreign DNA has resulted in unintended rearrangements occurring during the transformation or subsequent recombination.

This has been illustrated in Mon810 (the genetically modified insect resistant maize developed by Monsanto). So the knowledge gap is - has the post-genomic era understanding been integrated into biosafety research?

Secondly, in the biological context it has been found that there are distinct and biologically important differences in transgenic versus native versions of proteins.  So the knowledge gap is - how does the transgenic protein (protein produced by the modified gene) change structurally and functionally in different organisms? What is the potential impact on immuno-reactivity (the body’s ability to resist invasions against diseased organisms, poisons or foreign substances)? 

In the case of Cry 1A(b) (the protein derived from the bacteria, Bacillus thuringiensis (Bt), which targets the insect pest (the maize stem borer) in known immunogenicity research, a bacterial version, not plant (maize- derived version) is used for testing.

The plant version that is consumed has never been tested.

Is the bacterial version equivalent to the plant version? Are scientists promoting this technology using the appropriate tests for Bt, the maize we are all consuming? 

According to David Quist, a senior scientist from GenØk (a Norwegian public biosafety research institute), the actual structure and function of the plant Cry 1A(b) version protein is unknown, and no published studies of immunogenicity of the plant derived transgenic product exist. 

Thirdly, the environmental context of GMO introductions is another important consideration for biosafety. It is known that the environmental (biotic and abiotic) factors affect expression and gene function. Studies have shown toxic secondary metabolite production in genetically modified potatoes in response to stress. 

Asking the relevant biosafety questions of transgene expression is vital.

In South Africa where scientific research is biased towards the promotion of this technology and research in our parastatals and universities is significantly funded by biotechnology multinationals, can the public rely on government and scientific research institutions to address these knowledge gaps and answer the unknown?

In addition, will resources and funds be made available to address alternative research that supports more sustainable agriculture? 

Are risk assessments adequate when they are often done under agricultural conditions in a specific location? What happens when they are applied to a different location?

Quist points out that genes function differently in diverse contexts so there is need for a more integrated understanding of gene ecology for the prediction of GMO behaviour in a given context. Therefore, risk assessments must be case specific.

Despite the knowledge gaps about GM technology, South Africans are eating GM-maize that is not only a staple food, but also an important ingredient in many processed foods. This is a huge infringement on our choice and food sovereignty.  

Pressend coordinates the Trade Strategy Group (TSG) at the Economic Justice Network and Global Network Africa at the Labour Research Services in Cape Town. She is also an independent socio-political analyst on global issues related to trade, environment and climate change.

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hughlaue Verified user
23 Aug


Just saw Deborah Gracia's film on gmo (see Very scary and Monsanto comes out as positively evil - no exaggeration. It's the pretense that GMO will solve the food crisis and help the African poor that is so immoral, when control of the seeds and the whole agri-industrial machine for corporate profit is the primary motive. It's quite sickening.

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