Asthma study finds DNA culprit

HOPE HOLBOROW, SCIENCENETWORK WA

Western Australian medical scientists are making major contributions in the field of asthma research with the identification of variations in two DNA regions known to increase the risk of asthma. The international study released by The Lancet today was carried out by the Australian Asthma Genetics Consortium headed by Dr Manuel Ferreira from Queensland Institute of Medical Research, with key contributors to the research including four leading Western Australia Asthma Genetics groups. The study comprised a genome-wide association study in 2669 physician-diagnosed asthmatics and 4528 control patients from Australia. The Lung Institute of WA (LIWA), The Busselton Group, the Raine Cohort study and the School of Paediatrics and Child Health at UWA were involved in WA cohort. LIWA Director and senior author on the publication, Professor Philip Thompson explains the study involved comparing DNA of thousands of asthma patients with healthy individuals and combining the results with other international studies. “Two regions of the DNA were consistently different between asthmatics and non-asthmatics: one in the interleukin-6 receptor (IL6R) gene on chromosome 1, and the other [region] near a gene called GARP on chromosome 11,” Prof Thompson says. “Of these two, the first is particularly interesting because IL6R is a signalling molecule that plays an important role in the immune system and inflammation. It is involved in many diseases, including rheumatoid arthritis.” According to Prof Thompson, results suggest because of this genetic difference asthma patients produce more interleukin-6 receptor in the lung than non-asthmatics which, in turn, contributes to airway inflammation. The findings raise the possibility for the development of new drug treatments for asthma. “Medications acting on the IL6R may provide new treatment options,” he says. “This study has provided key biological insights into the complex mechanisms that cause asthma and illustrate the importance of key scientists combining their expertise to unravel, the molecular pathways involved in asthma.” Dr Alan James from the Busselton Group says asthma impacts one in ten Australians and can have a debilitating effect on their quality of life. “The Australian Asthma Genetics Consortium has brought together the top asthma experts from across the country,” Dr James says. World renowned asthma geneticist Prof Peter Le Souef from the UWA School of Paediatrics and Child Health was also involved in the project.