Multiple genes affect risk of asthma, hay fever, eczema: Study

Researchers have found a total of 141 regions in our genetic material that largely explain the genetic risk underlying asthma, hay fever, and eczema.

According to the study published in the journal 'Human Molecular Genetics,' as many as 41 of the genes identified have not previously been linked to an elevated risk for these diseases.

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 analysed 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.

The 41 new genetic finds were also tested in an independent group of individuals comprising 110,000 clients of the American company '23andMe.' This testing verified that most of these new genetic variants have an effect on the individual's risk of developing the disease.

Every '23andMe' participant, or client, has paid personally to send in a saliva sample, used by the company to analyse the person's DNA. The participants then receive information about whether they carry various inherited genetic traits that may elevate their risk of a number of diseases.

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," said a researcher.