About 80 per cent of people who have asthma also have hay fever or eczema. Photo: shutterstock.com

Weve long known that allergies such as eczema, hay fever and asthma are caused by a combination of genetic and environmental factors. But weve been unclear about which genes are responsible.

This week, my international research team published a study identifying ten genetic variants that increase a persons risk of developing allergies. The study, published in Nature Genetics, showed that the more variants a person has, the higher the risk of developing an allergic condition.

Allergies occur when the immune system thinks harmless substances such as dust are a threat. Photo: shutterstock.com

In Australia and New Zealand, about 30% of children have an allergy of some type. This occurs because their immune system incorrectly believes a harmless substance such as dust or pollen is a threat. These allergy-causing substances are called allergens.

Advertisement

An allergy develops when a particular type of cell from our immune system, B lymphocyte, produces antibodies against an allergen. This process often occurs at a young age and is known as sensitisation, that is, a person becomes sensitive to a particular substance in the environment.

From then on, if the same person is exposed to the same allergen, the antibodies produced by the B cells bind to the allergen. This triggers a series of reactions that culminate with inflammation appearing in the skin (eczema), nose (hay fever) or lungs (asthma). The symptoms of this inflammation are itching, sneezes and wheezes.

One in 10 Australians and New Zealanders have asthma. Photo: shutterstock.com

One in five Australians and New Zealanders will develop eczema in their lifetime; one in five will suffer with hay fever; and one in ten live with asthma, which can cause serious illness and can be fatal. About 80% of people who have asthma also have hay fever, and many also have eczema.

See the article here:
Genetics of allergies is nothing to sneeze at

Comments are closed.