Gene map of anti-malaria plant could boost supply

Scientists say they can boost supply of the key anti-malaria drug artemisinin

Global supply of a key, plant-based, anti-malaria drug is set to be boosted by a genetic study, scientists say.

Researchers have mapped the genes of Artemisia annua to allow selection of high-yield varieties.

The study, published in the journal Science, aims to make growing the plant more profitable for farmers.

"It's a major milestone for the development of this crop," Professor Ian Graham from the University of York in the UK told BBC News.

Short supply

The research has been welcomed by Dr Chris Drakeley, director of the Malaria Centre at the London School of Hygiene and Tropical Medicine. "Anything that enables an increased yield of product from something like Artemisia annua is a major step.

"This is the first line anti-malarial in nearly all endemic countries at the moment and supplies can be limited."

Artemisinin combination therapies, or ATCs, are used widely to treat malaria and are seen as the best solution to the parasite's increasing resistance to anti-malarial drugs.

Professor Graham, who led the study, hopes that new higher yielding and more robust varieties could increase global supply of the malaria treatment within three years.

"Our aim is to have hybrid seeds that can be released to farmers in the developing world by 2011 or 2012. With a year lag for planting, this would have an impact on supply in 2012 or 2013."

"We have to wait six to eight months from putting the seed in the ground to harvesting the crop and seeing how it has performed."

Dr Drakeley hopes the new varieties will become available quickly.

"This will allow an increase in the basic compound that forms ATC therapies. If they can get these seeds out in the timeframe they're talking about it'll be a major advance," he said.

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Professor Graham explains how the project works

To identify the best plants for hybrid seed production, researchers measured characteristics of individual plants, for example, the number of artemisinin producing glands on the leaf. They also performed tests to find the plants with the best genetic make-up.

The resulting seeds are being planted in field trials in China, East Africa, India and Madagascar. "We are expecting to end up with not just one hybrid.

Leaf gland which produces artemisinin

"Ideally we would like good hybrids for east Africa and good hybrids for India etc.," explained Professor Graham.

The study is the culmination of three years work funded by the Bill and Melinda Gates Foundation and the genetic maps and markers the researchers have identified will be made available for free all over the world.

"All the information and tools we've developed in this work are free for people to use for the charitable purpose," Professor Graham told BBC News.

"We're also working with seed producers so they can produce the seeds as cheaply as possible for the developing world."

Window of time

Scientists hope a better supply of the drug might also help with the problem of fake drugs being distributed.

Some treatments being sold have been found to have no drug content or to be substandard in quality. This can make them fatal or they can be more likely to encourage resistance rather than combat the disease.

"Hopefully, if the final product is easier and cheaper to procure after this development, it might lessen the production of counterfeit drugs," said Dr Drakeley.

Professor Graham believes that the development of drug resistance by the malaria parasite has made the work more urgent.

"We have a window of time when we can use artemisinin effectively, and we want to have a stable, reliable supply that can be used in that window," he said.