Should Genetic Modification And RNA Interference Be Used On Farm Animals?

The workshop highlighted the interlocking themes underlying the debate over livestock disease research, following a series of high profile epidemics and pandemics over the last two decades, including BSE, foot and mouth disease, bird flu, and PRRSV (Porcine Reproductive and Respiratory Syndrome Virus) in pigs, coupled with the public relations problems facing GM technologies.

It was clear that new technologies under the banner of GM have the potential to provide disease resistance with huge benefits for human health, animal welfare, and the agricultural sector, but only if public confidence can be restored. The ethical and societal dimension therefore featured strongly during the ESF workshop, according to convenor Bruce Whitelaw, Head of Developmental Biology at the Roslin Institute and Royal (Dick) School of Veterinary Studies in Scotland. "There was a very thought provoking presentation by Kenneth Boyd (from Environmental Research Institute in UK) on "what our conscience wants". This was one of the scene setting talks and was intended to make us consider up-front the ethical debate," said Whitelaw.

A major issue with GM was that it was deployed too soon with inefficient, inaccurate technology, and often for the wrong reasons, to benefit farmers and pharmaceutical companies rather than consumers. But the technical limitations are being overcome through new methods highlighted at the ESF workshop. "There was a very exciting presentation by Chamsy Sarkis (Centre National de la Recherche Scientifique in France) indicating the amazing new technologies and methods for gene transfer. The take home message is that soon we will be able to engineer the animal genome efficiently and in a precise manner," said Whitelaw.

At the same time GM technologies are being redirected towards animal health and welfare, according to Whitelaw. "The use of GM in farm species has been to-date focussed on high value products (e.g. animal bioreactors producing pharmaceuticals in milk). In the future much more effort will be applied to improve the health and welfare of animals through GM technology, with a second important topic being the generation of more appropriate animal models of human disease to enhance the development of better disease intervention strategies."

There has already been some success employing GM techniques to engineer disease resistance in animals. It is now possible to produce cattle lacking the gene that makes the prion protein responsible for BSE. Calves produced this way appear to be completely healthy, suggesting that the prion protein is not necessary, or that it has back up proteins that perform its functions. Either way, there is a real prospect of eliminating BSE from cattle livestock.

In the case of viral disease, other techniques apart from GM may be appropriate. The huge potential of RNA Interference was discussed at the conference, whereby the ability of viruses to produce the proteins they need for replication from the genetic information encoded in their RNA is blocked. This could help prevent pigs from contracting the deadly PRRSV, or chickens from getting bird flu.

But much more research is needed, and the ESF workshop helped bring together researchers with the relevant expertise in Europe. The workshop identified Europe's leading position in livestock disease research, spearheaded by the Scottish Network of Excellence "Development of Novel Technologies to Fight Viral Diseases in Farm Animals", which is a model for a possible Europe-wide consortium.

The ESF Exploratory Workshop on Genetic Models of Disease Resistance in Livestock was held in Edinburgh, UK in October 2007.

Each year, ESF supports approximately 50 Exploratory Workshops across all scientific domains. These small, interactive group sessions are aimed at opening up new directions in research to explore new fields with a potential impact on developments in science.