By Dr. Ronald Klatz, MD, DO
Nature Genetics has published an international study from the scientists at the UK National Heart and Lung Institute, the Trans-National Asthma Genetics Consortium, Paris Diderot University, University of Chicago, and the University of Colorado stating that they had worked together to discover 5 new regions of the genome that increase the risks of developing asthma.
Genetic loci linked with asthma are enriched in epigenetic marks that characterize gene enhancers, and shared associations of variants with autoimmune disease, asthma, and diseases with inflammatory components is another key factor that are significant findings of this study. Findings of this research open new opportunities for research with the goal of promoting the development of new therapies, and to elucidating biological mechanisms underlying asthma in relation to environmental exposure.
Asthma is a chronic inflammatory disease that is estimated to affect more than 300 million people around the world with close to 10-20% of that being children. Asthma carries as significant socio-economic impact. Asthma results from both exposure to lifestyle and environmental factors, and is characterized by clinical heterogeneity.
More than 45 research groups from Japan, Europe, Mexico, Australia, and North America were brought together by this international study. This allowed for pooling of data from the DNA of millions of polymorphisms throughout the genome, which included more than 142,000 asthmatic as well as non-asthmatic subjects of globally varied ancestry. The meta-analyses of the genome wide association research conducted within these diverse populations identified a total of 878 genetic variants coming from 18 loci that are associated with the risk of asthma.
This study suggests that there is a role of these variants in the regulation of immunologically related mechanisms because the genetic variants linked with the risk of asthma are preferably located near epigenetic markers in immune cells. The involvement of several identified candidate genes in the immune response to viruses is another source of concern, pointing out the role viral infections play in the development of the risk of asthma.
Autoimmune diseases and other diseases which are known to have an inflammatory component, including diseases such as cancers, cardiovascular disease, and neuropsychiatric diseases are also affected by the genetic variants linked with asthma, which adds weight to the importance of pleiotropy in multifactorial diseases.
These results serve to highlight the importance of large scale genetic studies to more efficiently characterize complex diseases. It also opens new opportunities for research integrating epigenomic and genomic data in combination with environmental exposures to promote the development of new therapies and to elucidate the physio-pathological mechanisms underlying asthma.
