One program in South Los Angeles aims to help parents of asthmatic children find these triggers and get rid of them.

NPR: Calif. Program Helps Rid Triggers of Asthma

The study showed that by substituting salmeterol for an alternative anti-inflammatory medicine, montelukast, outcomes for severely asthmatic children with the arginine-16 gene variant were substantially improved.

BBC: Is this the shape of medicine to come?

The research, carried out by Prof Somnath Mukhopadhyay, at the Brighton and Sussex Medical School and colleagues at the University of Dundee, focuses on the substantial minority of severely asthmatic children who respond poorly to the leading conventional drug treatment, Salmeterol.

BBC: Is this the shape of medicine to come?

Researchers also found feeding practices among children with asthmatic parents did not affect whether or not they developed the allergy.

BBC: A child is tested for allergic reactions.