CSIRO Plant Industry scientists developed the revolutionary gene silencing technology
Gene technology: gene silencing
CSIRO's gene silencing technology is enabling researchers around the world protect animals from diseases and develop new crop varieties.
5 March 2008 | Updated 20 March 2013
CSIRO's gene silencing technology
Developed at CSIRO's Plant Industry division the hairpin RNA interference (hairpinRNAi) technology is used to silence genes by turning the activity of the gene off or down.
The precise genetic blueprint of several animals and plants is now known. A key challenge now is to identify the function of each of these genes and to dissect their interactions with other genes. This exciting study of discovering gene function is known as Functional Genomics.
One of the strategies to determine gene function is to disrupt its activity and observe the effect on the organism – a process known as Reverse Genetics. hairpinRNAi is an effective technology for reverse genetics.
The search for genes that are responsible for valuable quality traits has been revolutionised by hairpinRNAi. It is now possible to discover these genes via a systematic, high-throughput process in animals with sequenced genomes, such as the cow and the chicken.
This technology is a powerful method to identify genes for targeted therapeutics, gene-based interventions and selective breeding.
hairpinRNAi can also be used to target virus and parasite genes in the development of precise therapeutics for diseases of companion, livestock and aquatic animals.
hairpinRNAi is already used extensively in plant genetics and CSIRO scientists are also applying this technology in the animal world.
Protecting chickens from influenza
The quest to enhance the natural immunity in chickens follows on from CSIRO's discoveries in plant diseases in the 1990s and the role of naturally occurring gene silencing mechanisms in plants and animals.
Gene silencing is naturally triggered when a viral pathogen invades a cell in a plant or animal and enables that plant or animal to stop the virus from replicating and causing disease.
Use of this natural mechanism by scientists is still at the early research stage and operates under strict guidelines and in full compliance with Australian legislation for gene technology.
The research is taking place in the world's most bio-secure research laboratory CSIRO's Australian Animal Health Laboratory in Geelong.
Influencing sex ratios in chickens
Researchers from CSIRO Livestock Industries and the University of Melbourne's Murdoch Children's Research Institute (MCRI) have solved the long-standing mystery of what determines sex development in chickens.
Using CSIRO-developed hairpinRNAi technology the scientific team successfully silenced a gene in chicken embryos, causing testis to become ovaries, bringing about a male to female sex reversal.
The research, which was published in Nature in 2009, could have significant benefits for animal welfare. In 2010 a new research project with industry was established with the aim of influencing sex ratios in poultry, particularly in the egg industry which does not require male chickens.
This discovery is not only a breakthrough in understanding sex determination in animals, it also has taken MCRI researchers closer to uncovering genetic causes of sex development disorders in humans.