The study, by the European-based GABRIEL consortium, identified several genetic variants that increase susceptibility to asthma in the population and scientists hope the findings will lead to the development of better therapies for the illness.
The GABRIEL consortium aims to identify the genetic and environmental causes of asthma in the European Community, in collaboration with groups in the UK, Canada and Australia.
The study group comprises 164 scientists in 19 countries from 23 different research groups, including The University of Western Australia’s Clinical Associate Professor Alan James, Dr Jennie Hui, Clinical Professor Bill Musk and Adjunct Professor John Beilby.
The researchers examined DNA samples from 10,000 children and adults with asthma, and 16,000 non-asthmatics to pinpoint differences in genetic code. In total, the consortium carried out more than half a million genetic tests on each subject, covering all genes in the human genome.
Professor James said the study had discovered several new genes that predisposed people to asthma.
“Some of these genes are in pathways that tell the immune system when the lining of the airways has been damaged. Other genes may control the rate of healing of the airways after they have been injured,” he said.
The GABRIEL team also looked at the genes which control levels of antibodies that cause allergies, known as Immunoglobulin E or IgE.
“Surprisingly, these genes did not have much effect on the presence of asthma, and the asthma genes had little effect on the levels of Immunoglobulin E. This means that the allergies which accompany many cases of asthma are likely to be a consequence of the asthma rather its cause,” Professor James said.
“Asthma has often been considered a single disease, but our genetic findings suggest that childhood-onset asthma may differ biologically from asthma that is acquired in adult life.”
The GABRIEL scientists found that the newly discovered genetic variants affected more than a third of children with asthma in their study, and that the genes had strong effects in cases of severe asthma. They suggested that concentrating on these genes would eventually lead to better therapies for the illness.
The scientists identified that environmental factors were very important in causing asthma to develop and the GABRIEL consortium continues to work on identifying environmental exposures that could protect against the illness.
The research was published in September in The New England Journal of Medicine.
Clinical Associate Professor Alan James (+61 8) 9346 2888
(UWA School of Medicine and Pharmacology)
Dr Jennie Hui (Adjunct Lecturer, UWA Centre for Genetic (+61 8) 9346 1931
Epidemiology and Biostatistics)
Janine MacDonald (UWA Public Affairs) (+61 8) 6488 5563 / (+61 4) 32 637 716