GM Science Review - Comments on First Report

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Name: Joanna Clarke Location (optional): Date: 9 October 2003
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GM Science Review (First Report)

I have read the GM Science Review (First Report) with interest and welcome the invitation for comments and the plan to consider if further issues should be addressed (page 5).


I note the use of the Corr Willburn report to frame the issues for consideration. The questions asked by the public with regard to 'Possible Risks to Health' (page 286) take the general form: could GM food undermine health: and, could it harm me/my family/future generations?

Bearing these in mind, there are two health issues which the panel have yet to address.

1. Human studies

Current safety testing is summarised (pages 69-70) as compositional equivalence of major constituents and known toxins plus the plants' phenotypic and agronomic characteristics, which may be followed by rodent feeding studies and farm-animal feeding values if appropriate. The next stage is post-marketing surveillance. Thus, safety assessment moves from nutritionally-focused, in vitro tests, to tests of limited relevance based on non-human data, and then to epidemiological studies which are recognised as being unlikely to establish a causal connection between GM consumption and any effect (page 73). There is a serious missing link here: carefully targeted human studies are needed to fill the gap between the preliminary evidence drawn from the plants themselves and from animal tests, and the final monitoring of the general population.

There is a recommendation (page 74) that holistic "testing paradigms" be researched to detect health impacts of unintended GM substances. This suggestion, as it stands, is unacceptably vague and contrasts markedly with the knowledge gaps and research issues for animal health in sections 5.5.6 and 5.5.8, where the problems have been pinpointed. The panel must refine and specify the avenues of investigation necessary within the context of human physiology.

2. Special needs

An increased risk to stressed animals due to gastro-intestinal tract changes was recognised as an important knowledge gap by the panel (page 107): in particular, gut permeability allowing the movement of material into the blood was one area of concern. This reasoning has not been extended to the many sectors of the human population who are likely to have a similar vulnerability.

Besides sectors of the population with, for instance, chronic diseases, the nutritional and digestive factors important to health in the elderly and the very young must also be the subject of special consideration.

In conclusion, the panel must extend its deliberations in both these vital areas and call for contributions from a wider expertise in, for example, human physiology, pathology and relevant clinical fields.


There is an inconsistency in the panel's consideration of the potential harmful effects of GM foods.

In the section dealing with likely future developments of nutritionally-enhanced animal feed using gene stacking, the question of increased risk is raised: "Would there be interactions between the various transgenes that were inherently different from the interactions with and between the thousands of other genes in the crop, both at the genetic and metabolic levels?" (page 107).

This is a key question, because the potential problems arising in the plant in any such expansion of genetic technology will be of an order of magnitude greater than those presently faced.

The inconsistency is that this same question of increased risk surrounds the current GM techniques as compared with non-GM breeding techniques, and for exactly the same reasons, but this is not acknowledged.

Non-GM breeding methods (outlined in pages 50-52) induce mutations or rearrangements in the plants' own DNA after which the natural plasticity of the living system adjust the metabolism as necessary; such responsiveness to change is necessary for life. GM breeding is unique in the insertion of DNA from several life-forms (plus synthetic sections) which are designed to control the host, meaning that the living system may be much less able to adjust itself, especially under stress. The potential for interference at both the genetic and metabolic levels to produce low, but harmful, levels of toxic by-products will be of an order of magnitude higher and more varied in

GM breeding compared with non-GM methods.

The panel seems to have avoided considering this aspect of GM technology except in the safer context of future developments and appears to be under-stating the risks.

Joanna Clarke
BSc. MIBiol. MIBMS CBiol.