Recombinant DNA technology provides a powerful tool to create new prod
ucts in many different fields. Agriculture and the agro-food industry
are two of them. Genetic engineering aims at improving the yield, the
nutritional quality or the technological value of food crops. The comp
osition of foods may also be modified in order to decrease the content
of toxic substances sometimes present in certain food crops. The expr
ession of recombinant proteins in foods must be carefully assessed as
proteins may induce allergic reactions in humans. Currently, the poten
tial allergenicity of a protein can be reasonably assessed only when t
he protein is known to trigger an immune response in sensitive subject
s. By contrast, the potential allergenicity of a protein of unknown al
lergenicity cannot be easily predicted as no immunoserum of allergic s
ubjects is available. That is why an allergenicity assessment model fo
r any genetically engineered food should be designed. Even though the
gene product is completely characterised in the transgenic product, th
is does not necessarily provide information on its potential allergeni
city. Animal models, in vitro tests and protein structure should be ta
ken into account. Besides, allergenicity is a biosafety issue, for it
deals with human health. The issue of food allergies in food safety sh
ould not be neglected, as an allergic reaction can be life threatening
.