Edinburgh scientists modify bird genes to halt lethal virus

Published on 13/01/2011 17:20

Chickens have been genetically modified to prevent them spreading potentially deadly bird flu.

The research by scientists at Edinburgh and Cambridge Universities may lead to ways of halting bird flu outbreaks within poultry stocks.

As well as protecting the health of poultry, it could reduce the risk of a killer pandemic among humans.

Bird, or avian, flu does not easily infect humans but when it does the effects can be serious.

One strain, H5N1, has caused about 300 deaths since the mid-1990s and kills about 80 per cent of all those it infects.

Experts fear a mutated version of the virus that transmits easily from person to person would have the potential to claim millions of victims around the world.

Professor Helen Sang, from the Roslin Institute at the University of Edinburgh, said: "The results achieved in this study are very encouraging. Using genetic modification to introduce genetic changes that cannot be achieved by animal breeding demonstrates the potential of GM to improve animal welfare in the poultry industry.

"This work could also form the basis for improving economic and food security in many regions of the world where bird flu is a significant problem."

Co-author Dr Laurence Tiley, of Cambridge University, said: "Chickens are potential bridging hosts that can enable new strains of flu to be transmitted to humans. Preventing virus transmission in chickens should reduce the economic impact of the disease and reduce the risk posed to people exposed to the infected birds.

"The genetic modification we describe is a significant first step along the path to developing chickens that are completely resistant to avian flu."

The researchers, whose work is reported in the journal Science, introduced a gene that interferes with the replication machinery of the virus.

When the transgenic chickens were infected with avian flu, they became ill but did not transmit the virus to other normal birds kept in the same pen with them.

The gene is expected to work against all strains of bird flu, and the virus cannot easily evolve to escape its effects.