Gene study could hold key to more anti-malaria treatments

Published on Sunday 10 October 2010 15:35

SCOTTISH scientists have identified genes that make some malaria-carrying mosquitoes resistant to insecticide.

Researchers have pinpointed a gene that enables the parasite that causes the infection to resist treatment with the plant-based remedy artemisinin.

They hope the breakthrough could boost efforts to prevent the disease, one of the biggest killers in the developing world.

In many countries where the parasite has developed resistance to previously effective common treatments such as chloroquine, artemisinin remains the only effective treatment against the infection.

However, malarial resistance to artemisinin appears to be developing, potentially creating problems in controlling malaria.

Scientists said that identification of this gene paves the way for further studies that could eventually help control the development of resistance to artemisinin and lead to more effective drugs for human malaria.

The study, by scientists from the University of Edinburgh and the New University of Lisbon, used emerging technology to scan the genetic fingerprint of drug resistant parasites that infect rodents.

Dr Paul Hunt, from the University of Edinburgh's School of Biological Sciences, said: "This knowledge from rodent malaria parasites opens up new directions that will allow this gene to be investigated in human malaria.

"This may help track the evolution of drug resistance and may eventually enable the design of alternative, effective drugs."

The technology used by the scientists allows rapid identification of genes that enable the parasite to withstand existing drug treatments.

The study, published in BMC Genomics, was funded by the Medical Research Council.

There are estimated to be between 300 and 500 million cases of malaria each year, occurring in more than 90 different countries, according to the World Health Organisation (WHO).

In 2008, malaria caused nearly one million deaths, mostly among African children, the WHO said.

The disease is caused by a parasite transmitted by certain types of mosquitoes, mostly of the genus anopheles. Symptoms usually begin with a high fever, neck and back pain and progress to shivering, vomiting and convulsions. Children are particularly vulnerable.

Although pills exist that can help prevent malaria, there is no vaccine. Preventative medication is used mainly by travellers.

One of its most recent high profile sufferers was celebrity singer Cheryl Cole who contracted the disease after being bitten by mosquitoes during a holiday in Tanzania.

In September 2003 the world's richest man Bill Gates donated about 100 million to fund research into the mosquito-borne disease.The money from the Bill and Melinda Gates Foundation will be used to provide three research grants which include developing a vaccine, to use existing drugs to reduce the number of infections in babies and thirdly to develop new medicines to tackle drug resistant strains of the disease.