Asthma gene mutation discovered on island

Researchers have identified a mutated gene that makes people susceptible to asthma, having discovered it on one of the world's most isolated islands.

Sequana Therapeutics analysed DNA from about 300 people on Tristan da Cunha, an island in the south Atlantic, about 1,500 miles from South Africa. About 30 per cent of the island's residents have asthma, apparently passed on from an original settler.

The pinpointing of the mutated genes eventually could help identify people at risk of getting sick, and also could suggest new drugs for treatment.

"We found a difference - a change in that DNA that is different in people who have asthma than those that don't have the disease," said Bob Giargiari, of San Diego-based Sequana.

The researchers said that, of the estimated 15 million Americans with asthma, up to 10 per cent seemed to have a genetic predisposition to the disease.