IMPORTANT LEGAL NOTICE - The information on this site is subject to a disclaimer and a copyright notice
Banner Research
  European Commission   > Research > GMO
EC-sponsored Research on Safety of Genetically Modified Organisms - A Review of Results
imageIntroductionimage Research areasimage Foodimage Project 07
Graphic element Graphic element Graphic element

 button Introduction
 button Foreword
 button Research areas
imageimageimage Plants
imageimageimage Plant  microbes
imageimageimage Biocontrol
imageimageimage Food
imageimageimage Bioremediation
imageimageimage Tools
imageimageimage Fish
imageimageimage Vaccines
 button Index of participants
image Safety evaluation of horizontal gene transfer from genetically modified organisms to the microflora of the food chain and human gut

Background and objectives

Horizontal gene transfer (HGT) as a biosafety issue has been addressed in several studies which have mainly focused on the transfer of antibiotic resistance from genetically modified (GM) plants to soil- and plant-related micro-organisms. HGT to bacteria in these environments has been shown by marker rescue experiments via homologous recombination. However, HGT via transformation of bacteria in the food chain cannot be excluded. Free DNA persists in some materials for weeks, and furthermore, some bacteria develop natural/chemical competence to take up DNA from the environment. In addition, in the gastrointestinal tract of man and husbandry animals, DNA may remain stable for some time, particularly in the colon. The main objective of this project is to quantify the risk of HGT from genetically modified organisms (GMOs), and food derived thereof, to the microflora of the food chain and the human gut. In addition to analysis of gene transfer frequencies, hazards will be identified, data of exposure to GMO food will be collected and the impact will be addressed to quantify and precisely define the risks of HGT. In particular, selective conditions are particularly relevant for antibiotic resistance marker genes. Therefore, the relevance of a particular antibiotic as a therapeutic agent will be dealt with in the risk evaluation. This project also aims to evaluate models which can be used to study these HGT events.

Approach and methodology

To collect data for an evaluation of HGT from transgenic food products, in vivo and in vitro gastrointestinal tract model systems will be studied, evaluated and validated. Since gene transfer can occur via different mechanisms depending on the genetic background, different donor/recipient systems will be studied. In addition to examining these mechanisms, other parameters relating to the frequency of HGT will be analysed, such as survival of bacteria, stability of DNA, development of competence for transformation, possibility of recombination, and selective pressure. The data will be evaluated to quantify the risk of HGT based on the genetic background, daily intake of transgenic DNA, formulation of the food product, and the nature of marker genes.

Main findings and outcome

In the project that is underway, the consortium will collect relevant information on the above issues by using food, rumen, and rodent models and computer controlled gastrointestinal tract model (figure). Stability of DNA and GMOs, and HGT will be analysed by molecular monitoring systems based on DNA hybridisation, polymerase chain reaction, culturing methods and cell sorting.

  image image Computer-controlled gastrointestinal tract model.


The results of this study will be important for biosafety issues relating to the consumption of food prepared using GMOs.

image imageimage image
imageResearch project

Contract number

February 2000 - February 2003

J.M.B.M. van der Vossen
TNO Nutrition and Food Research Institute
Zeist (NL)



H.J.M. Aarts
State Institute for Quality Control of Agricultural Products (RIKILT)
Wageningen (NL)

W.P. Hammes
University of Hohenheim
Stuttgart (DE)

G. Corthier
Jouy-en-Josas (FR)

B.B.L. Lund Jacobsen
Institute of Food Safety and Toxicology
Søborg (DK)

A. Haslberger
University Vienna (AT)

Previous project | Food contents | Next project | Top