Madam, - It is legitimate for people to be concerned about the health and environmental impacts of GM food, and those who believe in the technology need to win the public round. However, what is not legitimate is to try to scare people with misleading and erroneous information, as in the latest diatribe by Dr Elizabeth Cullen (Opinion & Analysis, May 17th).
An exhaustive critique would take too long, so I'll restrict myself to a few of the more glaring points. Dr Cullen states: "The piece of DNA is generally inserted into a virus, which then infects the targeted cell". This is not true. If a biological vector is used (which is not always the case) it is invariably bacterial, not viral. I would be most concerned if my GP did not know the difference between bacteria and viruses.
Dr Cullen writes about "concerns in relation to the health impacts of genetically engineered food, and in particular, the decision to grant permission for the planting of genetically engineered potatoes in Ireland". This is a non-sequitur. Field trials of potatoes will not involve human consumption, and therefore health impacts do not arise.
Dr Cullen refers to a number of animal feeding trials, without citations, without commenting on the particular recombinant proteins concerned, and without indicating that these GM plants were not developed as new food varieties. Of course if you express a toxic protein in a plant (as in the well-known potato experiments by Dr Pusztai, which I presume Dr Cullen is referring to), it will cause adverse affects in feeding trials.
This is not a feature of GM technology, and the tendency of GM opponents to clump together all GM plants as if they were the same, is arguably their most dishonest tactic.- Yours, etc,
PHILIP J DIX, Maynooth, Co Kildare.