Asthma is a condition in which a person's airways become inflamed and produce extra mucus. In a breakthrough discovery, Australian scientists have revealed that a gene named PAG1 is more likely to increase inflammation in asthmatics. The study findings contradict most previous studies on the function of the PAG1 gene in the immune system and provides a potential new treatment target.
Dr. Manuel Ferreira from QIMR Berghofer's Asthma Genetics laboratory said, "In a large genetic study last year we had identified a previously unknown genetic variant which increased the risk of asthma and allergies by about 20%, but since it wasn't immediately obvious which gene that variant impacted, we designed a series of molecular experiments to identify that target gene. We now know that while the risk variant was located a considerable distance from PAG1, it is able to reach that gene through a process known as DNA looping, and it increases PAG1 expression in people with asthma."
Dr. Ferreira further added, "In most of these studies in animal models and human cell lines there was no stimulation of the immune system with an allergen or virus, two key stimuli that trigger asthma. I believe that the function of PAG1 may be dependent on the context of the immune challenge, in the case of an allergen or virus it may have a pro-inflammatory response."
Dr. Ferreira identified a gene variant in 2011 that led to a clinical trial underway in Brisbane which is testing whether a drug used to treat rheumatoid arthritis could be useful in treating asthma. He stated that between 30-50% of people have an allergy of some kind, often developed in their early years.
The research has been published in the American Journal of Human Genetics.