All young asthma suffers are given a blue inhaler to relieve their symptoms, but if your child is one of thousands who use a green or purple inhaler to control severe asthma they could be taking medication that has little or no effect.
A group of scientists have discovered that a spit test can identify these patients and their findings could open the door to personalised medicine in childhood asthma.
The research found DNA can be used to identify severe asthma sufferers who do not respond to salmeterol, the drug used in Seretide and Servent inhalers to relax the airways to the lungs.
The drug, given to children who cannot control their condition with the widely-used blue inhaler, relaxes the airways by targeting the beta-2 receptors. In one in seven people these receptors are a different shape making it difficult for the salmeterol to recognise them and take action.
Scientists at the Brighton and Sussex Medical School and the University of Dundee looked at 62 children with this genetic mutation. The results of the study were published in the Clinical Science journal.
It found that DNA in a child’s spit could help identify the shape of their beta-2 receptors and therefore indicate whether salmeterol would have any effect on their condition.
As part of the study half the patients continued with salmeterol while half were given an alternative drug, montelukast – those children experienced improved symptoms and, as a result, had less time off school.
Although not yet available for use in doctors’ surgeries, the genetic test would cost about £15 to perform and could help identify the estimated 15,000 children in the UK with the genetic mutation. More research would be needed before such a test could be introduced.