Synthetic life – the double-edged sword

Today, it was announced that Craig Venter and his associates have created an artificial bacterial cell that is capable of replication. This is a remarkable achievement and has received a great deal of attention in the press. However, I will pass over most of the implications of this work to focus on those aspects most relevant to influenza pandemics.

There are many technical breakthroughs associated with the production of artificial bacteria, but the central achievement was the chemical synthesis of an over million nucleotide long molecule of DNA that codes for a bacterial chromosome. This tour-de-force redefines the limits of what is possible in DNA synthesis. This same group had shown that the much smaller genomes of viruses could be produced with similar techniques back in 2003. The polio virus genome was produced synthetically in 2006.

How can the new techniques be used? Although the specific approach has not yet been discussed in detail, Dr. Venter is working with Novartis on using this technology to produce a flu vaccine within 24 hours. Such a vaccine may be available as soon as next year.

From the Winnipeg Free Press, May 21, 2010

The U.S. National Institutes of Health is also funding a project with pharmaceutical giant Novartis to try to make synthetic DNA that could be used to manufacture vaccines in 24 hours instead of the weeks to months it normally takes.

“When you see how long it took to get an H1N1 vaccine out, we think we can shorten that process quite substantially,” he [Dr. Venter] said. Artificial DNA might also solve the problem of developing vaccines for quickly evolving viruses like the common cold or HIV.

From the NewScientist, May 20, 2010

Venter’s work was a proof of principle, but future synthetic cells could be used to create drugs, biofuels and other useful products. He is collaborating with Exxon Mobil to produce biofuels from algae and with Novartis to create vaccines.

“As soon as next year, the flu vaccine you get could be made synthetically,” Venter says.

This would be a welcome change from the current antiquated approach to making flu vaccines. The long delay in the production of the pandemic H1N1 vaccine likely resulted in many deaths.

Some critics of biotechnology have raised concerns about the safety implications of laboratory production of bacteria. I think these critics are misguided. It has been possible to genetically modify bacteria for decades. Further, it is relatively easy to stop the spread of bacterial disease. Hence, they are not likely to be effective agents for terrorist attacks. However, I think some of the reassurances about gene synthesis are also misguided.

From the Los Angeles Times, May 20, 2010

…it is highly unlikely that the technology could be put to use by terrorists because of the great cost and the amount of time required — about $40 million so far over 15 years.

40 million dollars would not be a very large price to pay for a formidable bioweapon. Certainly, this is much less than would be required for a nuclear weapon. The statement about 15 years is just plain silly. It took 15 years to develop the technology. Now that it exists and has been described in detail, it can be applied in a much shorter time frame.

However, I think that the focus on synthetic bacteria as agents of bioterrorism is misplaced. Viruses are far more dangerous and much easier to synthesise. The number of antiviral agents are small and can easily be circumvented by tweaking viral sequences. Viruses are much more contagious than bacteria and can be extremely lethal. Viral genomes are orders of magnitude smaller than bacterial genomes and hence much easier to produce via gene synthesis. You can read more about how this could be done here.

The investigators who produced the laboratory-generated bacteria included an artificial nucleotide sequence that serves as a watermark that can easily identify it as synthetic. It was suggested that anyone working with artificial life forms also identify their creations with these watermarks. This is a good idea as it would facilitate identification in case of an accident. However, it seems unlikely that a terrorist or military lab developing a bioweapon would comply with these precautions. It is also telling that the investigators felt the need to explicitly label their creation with a distinct sequence. They realised that otherwise it would have been difficult to distinguish between a lab-generated synthetic and the real thing.

The technology to produce lab-generated, untraceable viruses that could be used as bioweapons has existed for several years. At the current time, only a few countries are likely to have the resources to produce such viruses. That will change as the technology becomes better known. The only defense against such weapons is a resilient society willing to impose movement restrictions until a vaccine can be produced and distributed.

If gene synthesis technology can be used to produce vaccines within 24 hours of identifying a novel infectious agent, we’ll all be a lot safer.

Reference

Gibson et al. (2010) Creation of a Bacterial Cell Controlled by a Chemically Synthesized Genome. Science.

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