Genetic mapping completed of plant that is the source of key antimalarial drug

14 Jan 2010

Paul Chinnock

Source: TropIKA.net

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Assessing Artemisia plants to determine the traits responsible for improved yields. CNAP.

Genomic research is now clearly established as an important part of efforts to defeat the infectious diseases of poverty. It is nearly eight years since the genomes of Plasmodium falciparum (the cause of the most serious form of malaria) and of Anopheles gambiae (the most important of the mosquitoes that transmit malaria) were both sequenced (1). More recent achievements include the publication of a genetic map of the parasite responsible for schistosomiasis – see TropIKA.net News. But it is not only the genomes of parasites, vectors and humans that have been the focus of research; scientists at the University of York, UK have been studying the genome of the plant from which the drug artemisinin – now the mainstay of malaria treatment – is sourced.

In this week’s issue of Science, researchers from York’s Centre for Novel Agricultural Products (CNAP) will publish the first genetic map of the medicinal herb Artemisia annua, plotting the location on the plant’s genome of genes, traits and markers associated with high performance. This will enable scientists to recognise young plants as high performers from their genetics. It will also inform the selection of suitable parent plants for breeding experiments.

There a rapidly growing demand for artemisinin for use in artemisinin-combination therapy (ACT) and the drug is often in short supply. Higher yielding varieties of Artemisia would help address these shortages.

The genetic map has been validated in glasshouse experiments that found the top-performing plants had elevated frequencies of genetic indicators for high yield.

The project is led by Professor Dianna Bowles and Professor Ian Graham. Professor Graham says. “The map is already proving to be an essential tool for us. With our new understanding of Artemisia genetics, we can produce improved, non-GM varieties of Artemisia much faster than would otherwise be possible”. This speed is essential. “We intend to get high-yielding seed to farmers in the next 2-3 years in order to supply soaring demand for malaria treatments”, explains Professor Bowles. “This is a really tight deadline and we can only do it with the benefit of the new knowledge provided by the map.” The work demonstrates how modern genetics is shortening the timescales needed to turn a wild plant species into a domesticated crop.

CNAP hopes to create new varieties that can be grown by many thousands of small scale growers in the developing world, for whom the Artemisia crop is an important source of income. The project has just received its second grant from the Bill & Melinda Gates Foundation. This grant will support final development of the new varieties and their delivery to Artemisia producers in Africa and Asia.

CNAP is part of a project known as the Artemisia Enterprise – see TropIKA.net News.

Reference

Aultman KS, Gottlieb M, Giovanni MY, Fauci AS (2002). Anopheles gambiae genome: completing the malaria triad. Science; 298(5591):13. Available from: http://www.ncbi.nlm.nih.gov/pubmed/12364752