Battling malaria

"Scientists battling malaria have earned a major victory", according to a Nature Genetics study. "Combating malaria resistance is nothing short of an arms race," says author and pediatrics professor, Dr. Philip Awadalla, from the Universite de Montreal. "As the malaria pathogen evolves, researchers must evolve with it to find ways to counter the disease."

Every year approximately 250 million people contract malaria. "Malaria is transmitted when people are bitten by infected mosquitoes. According to the World Health Organization, malaria symptoms include fever, headaches, vomiting and appear within 10 to 15 days after an infected mosquito bite." If left "untreated, malaria can be life-threatening" and may kill "an estimated five million people yearly." At the current level of malaria treatment one million people die annually, and most of those who die are young children.

The team at Universite de Montreal is deciphering the deadly parasite in an effort to eradicate the disease. This "international group of researchers has used genomics [study of organisms' genomes] to decode the blueprint of Plasmodium falciparum -- a strain of malaria most resistant to drugs that causes the most deaths around the world. The discovery may lead to advanced pharmaceuticals to fight the disease and prevent drug resistance".


"The team decoded 200 malaria samples from Asia, Africa, Central America, South America and Papua New Guinea. Their goal was to identify how Plasmodium falciparum strains were becoming resistant to the eight anti-malaria drugs currently available." The team noted how there is "substantial genetic differences in malaria around the world. What has occurred is a combination of genetic drift, where genes segregated over space and time from differential environments, immune pressures and exposures to drugs."

Research discovered that "Plasmodium falciparum recombined fastest in Africa...New clues garnered by this study...will allow pharmaceutical companies to create treatments that target the evolving malaria genome."

Sources:

Mu et al. Plasmodium falciparum genome-wide scans for positive selection, recombination hot spots and resistance to antimalarial drugs. Nature Genetics, 2010; DOI: 10.1038/ng.528

University of Montreal (2010, February 18). Genomic warfare to counter malaria drug resistance. ScienceDaily. Retrieved February 20, 2010, from http://www.sciencedaily.com¬ /releases/2010/02/100216140146.htm

Lost Code

Although made of few parts, the complete DNA content or genome of a species is extensive and complicated. Plasmodium falciparum, "the most deadly form of malaria", has about 5,300 genes. "Up until now, scientists [had] a good understanding of the gene functions for only about half" of the genes.


Plasmodium falciparum is a tiny parasite that infects the blood of mammals through mosquito bites and is responsible for approximately 1 million human deaths each year. "Using transcriptional profiling," a process by which "gene expression (activity) patterns" are revealed, the research team lead by Prof Zbynek Bozdech (Nanyang Technological University) "has successfully uncovered the gene functions for almost the entire genome, with more than 90 percent of the gene functions from the previously unknown half now better understood."


"Transcriptional profiling is the measurement of the activity of thousands of genes at once," in order to "create a global picture of cellular function. These profiles can, for example, distinguish between cells that are actively dividing, or show how the cells react to a particular treatment. This outcome in infectious disease pathology could potentially be the decade's big breakthrough as it has yielded critical information about how the malaria parasite...responds to existing compounds with curative potential."


"Preventing malaria infection is important because resistance to anti-malaria drugs is a growing problem worldwide. There is currently no vaccine for malaria, which is widespread in poorer countries where it remains a hindrance to economic development. Also of growing concern to scientists is the confirmation of the first signs of resistance to the only affordable treatment left in the global medicine cabinet for malaria: Artemisinin."


"In successfully using transcriptional profiling to study the behavior of the malaria parasite, ...researchers have ventured into the unknown and paved the way for future breakthroughs in healthcare."

Sources:
Gastin, George. "GenomeGradient.jpg" [Photo hosted by wikimedia, shared under CC license] http://commons.wikimedia.org/wiki/File:Genome_gradient.jpg

Nanyang Technological University (2010, February 6). World's first in-depth study of the malaria parasite genome. ScienceDaily. Retrieved February 7, 2010, from http://www.sciencedaily.com /releases/2010/02/100205102607.htm