AS agents of death and misery, few organisms can compete with the malaria parasite and the mosquito that transmits it. So there can be not a shred of doubt that last week鈥檚 unveiling of their genetic blueprints is well worth celebrating. Hundreds of researchers worked for years on these projects, many no doubt keeping long hours for less than wonderful remuneration. They can and should feel proud.
Nevertheless, scientific milestones do not in themselves save lives or eradicate disease, and there has seldom been a more timely moment to remember this.
In recent years scientists have unveiled so many genomes to such great fanfare that you鈥檇 be forgiven for thinking these blueprints offer an ironclad guarantee of success. As long as we diligently invest in high-tech 鈥済enomics鈥� research, we tell ourselves, these blueprints are certain to speed up the fight against disease and one day turn into panaceas. Malaria, more than any other disease, exposes the laziness of such thinking.
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Take the goal of designing better drugs and inventing insecticides that are more precise and environmentally friendly than the ones used today. The malaria parasite鈥檚 genome is made up of some 5300 genes, many of which will undoubtedly encode new drugs targets (see 鈥淲eedkillers could wipe out malaria鈥�). And some of the 13,000 genes in the mosquito鈥檚 genome will undoubtedly encode new targets for insecticides.
So what鈥檚 the catch? One problem is that unless these compounds are affordable they won鈥檛 save many lives. The genome teams have, to their credit, made the blueprints available to all. But this will not stop companies and universities patenting individual malaria or mosquito genes, or drugs and insecticides invented on the back of these blueprints. Many African countries cannot afford DDT, never mind expensively tailored insecticides.
And if affordability sounds like a politically correct side issue that can be safely left till later, consider this. Drug resistance in malaria is a growing problem 鈥� yet it doesn鈥檛 have to kill. It is perfectly possible to treat parasites that are immune to older malaria drugs, such as chloroquine, with newer drugs. The problem is these drugs are beyond the pockets of many countries, despite large discounts from manufacturers. If genome research produces more of the same, and is not backed up with money to buy drugs, it will not ease the plight of the world鈥檚 poorest.
Nor will it help if governments and research charities now opt to throw the bulk of their resources into mining these two genomes at the expense of established, and sometimes less glamorous, lines of research that will probably deliver benefits much sooner. Plenty of potential anti-malaria insecticides already languish on chemists鈥� shelves, and a handful of new experimental malaria drugs are showing real promise. Diverting money away from testing them could seriously hinder progress.
As it could if money is pulled away from established attempts to develop a malaria vaccine. It鈥檚 true that the malaria genome will help researchers discover malaria molecules that stimulate the human immune system and so qualify as candidates, or 鈥渁ntigens鈥�, for making a vaccine. But they already have more malaria antigens than money to test them. The big challenge is how to make such molecules stimulate a strong and lasting immune response to a parasite with such a complex life cycle. Having a genome is no guarantee of success. The HIV genome has been in the bag for 15 years. Yet there is still no effective HIV vaccine.
杏吧原创s are even more divided about the value of creating transgenic mosquitoes that can鈥檛 transmit malaria. Discovering mutations or genes capable of making mosquitoes malaria-proof is not too hard. The challenge is getting such genes or mutations to spread into wild populations of mosquitoes and stay there.
Unless this problem is solved, GM insects will not deliver lasting benefits. Worse, fear some experts, temporarily eliminating malaria could result in people losing natural immunity, making the disease more rampant if it comes back. Many African countries are already wary of importing GM food aid. They will not be queuing up to be guinea pigs in GM mosquito research.
In the long run, basic genome research is likely to pay off. In the meantime, we must ensure the vortex of hype it generates does not suck in resources that would be better deployed fighting malaria on other fronts.