New study found a total of 141 regions (genes) in our genetic material that primarily explains the genetic risk underlying asthma, hay fever, and eczema. As many as 41 of the genes recognized have not earlier been linked to an elevated risk for these diseases. The findings of the study are published in the journal Human Molecular Genetics.
The risk of developing asthma, hay fever, or eczema is affected by genes, environment, and lifestyle factors. Many patients diagnosed with one of these diseases also develop the other two at some stage in life. Although previous studies have found many genes that exert an effect on these diseases, research has been unable to explain the whole genetic background to the origin of asthma, hay fever and eczema.
In this study, which is the largest of its kind to date, researchers have analyzed self-reported data from 350,000 participants in Britain's UK Biobank. Millions of gene positions were tested for their effect on people's risk of being diagnosed with asthma, hay fever, and/or eczema.
Researchers can apply to obtain results in which 23andMe have analyzed clients' DNA, to find additional genetic variants that affect the disease(s) analyzed (in this case asthma, hay fever and/or eczema). The researchers can never access any given individual's results, nor can they link their findings with specific individuals (the data are deidentified).
"For those interested in taking part in similar studies where they can get information about their own genetic inheritance, we'd like to point out that the results you can read from DNA in similar studies relate only to people's disease risk, which doesn't correspond to a diagnosis. External factors also affect our risk for these complex traits, and an elevated risk doesn't mean we're going to develop the disease," says Weronica Ek, a researcher at the Department of Immunology, Genetics, and Pathology at Uppsala University, who headed the study.
The study showed that a large number of the genes identified entail a raised risk for all three diseases. This, in turn, shows that the elevated risk of suffering from allergy when asthma is diagnosed, or the elevated risk of asthma when an allergy is diagnosed, seems to be largely due to genetic factors. The study was also able to identify several genes that boost the risk of one of these diseases in relation to the others, which demonstrates that a number of more disease-specific effects also exist.
All three diseases arise through a complex association among several genes and also with environmental and lifestyle factors. To be able to improve the patients' everyday lives, it is important to develop drugs that are adapted to individual patients' genetic risks, and also to understand how our environment and lifestyle can prevent disease and improve symptoms of the disease.
"The results from this study are helping us to reach a greater understanding of why certain individuals are at higher risk of developing asthma and allergies, and we hope the results will be put to use both in clinical diagnostics and in drug development," Ek says.