www.checkbiotech.org ; www.raupp.info ; www.czu.cz

Tomatoes, genetically modified to produce 90 per cent less of the allergen,
profilin, represents "a future trend in allergen avoidance," said the German
researchers behind a new study, October 2006 by Stephen Daniells.

But despite this offering an alternative approach, one of the main
challenges of this approach will not be technical but consumer attitudes and
regulations regarding genetically modified organisms (GMO), particularly in
Europe.

An estimated four per cent of adults and eight per cent of children in the
380m EU population suffer from food allergies, according to the European
Federation of Allergy and Airways Diseases Patients' Associations.

Dr. Ronald van Ree from the University of Amsterdam recently told attendees
at the BA Festival of Science in England that recent advances in
biotechnology have identified the specific molecules in foods that induce
food allergies. Such knowledge could also lead to genetic engineering
techniques to change these molecules so that they no longer cause an
allergic response, he said.

And the research, by scientists at the Friedrich-Alexander University
Erlangen-Nuremberg and Paul-Ehrlich-Institut, represents one of the first
reports of a genetically engineering to reduce a food allergy.

While considerably less common than peanut or cows milk allergy, up to 16
per cent of people with food allergy are said to be allergic or sensitive to
tomatoes, "indicating that tomato is a relevant allergenic food," said lead
author Lien Quynh Le in the Journal of Allergy and Clinical Immunology
(published on-line ahead of print, doi:10.1016/j.jaci.2006.06.031).

Indeed, "three tomato allergens have been identified thus far and were
included in the official allergen list by the International Union of
Immunological Societies Allergen Nomenclature Subcommittee," said Quynh Le.

The researchers used the RMA interference approach to silence two genes (Lyc
e 1.01 and Lyc e 1.02) associated with profilin production, a small protein
that is said to contribute to fruits and vegetables allergy, and produce
transgenic tomatoes.

The resultant GM tomatoes were found to have contain about 10 per cent of
the profilin levels of 'wild-type' tomatoes.

Extracts of both the GM and wild-type tomatoes were prepared and 16 people
with diagnosed tomato allergies were recruited to test for an allergic
response using a skin-prick test.

The researchers report that when volunteers were sensitive to only one
tomato allergen, the GM tomatoes significantly improved the allergic
response. However, when patients were sensitive to several tomato allergens
the response was less pronounced.

Lien Quynh Le and her co-workers said that to create truly hypoallergenic
tomatoes, the described strategy of using RNAi would have to be extended to
silence multiple genes.

"Our findings demonstrate the feasibility of creating low-allergenic food by
using RNA interference (RNAi). This approach constitutes a future trend in
allergen avoidance," said the scientists.
[www.foodnavigator.com]

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