Synthetic DNA may yield new life forms

Until recently, even the most sophisticated laboratories could make only small snippets of DNA...

Until recently, even the most sophisticated laboratories could make only small snippets of DNA — an extra gene or two to be inserted into corn plants, for example, to help the plants ward off insects or tolerate drought.

Now, researchers are poised to cross a dramatic barrier: the creation of life forms driven by completely artificial DNA.

Scientists in Maryland have already built the world’s first entirely handcrafted chromosome — a large looping strand of DNA made from scratch in a laboratory. In the coming year, they hope to transplant it into a cell, where it is expected to “boot itself up” like software downloaded from the Internet.

The cobbling together of life from synthetic DNA will be a watershed event, blurring the line between biological and artificial and forcing a rethinking of what it means for a thing to be alive. Some experts are worried that a few maverick companies are already gaining monopoly control over the core “operating system” for artificial life and are poised to become the Microsofts of synthetic biology.

So far, synthetic biology is still semi-synthetic, involving single-cell organisms that have a blend of natural and synthetic DNA. The cells can reproduce, a defining trait of life. But in many cases that urge has been genetically suppressed, along with other “distracting” biological functions, to maximise productivity.

J Craig Venter, chief executive of Synthetic Genomics in Rockville wants his cells to make exotic fuels for vehicles, to fill a market that has been estimated to be worth $1 trillion.

Venter has now built the first fully artificial chromosome, a strand of DNA many times longer than anything made by others and laden with all the genetic components a microbe needs to get by.

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The plan is to mass-produce a plain genetic platform able to direct the basic functions of life, then attach custom-designed DNA modules that can compel cells to make synthetic fuels or other products.

Yet another application is in medicine, where synthetic DNA allows bacteria and yeast to produce the malaria drug artemisinin far more efficiently than it is made in plants.

“Synthetic biology means cheaper and widely accessible tools… that could pose grave threats to people and the planet,” stated a recent report by the Ottawa-based ETC Group, one of dozens of advocacy groups that want a ban on releasing synthetic organisms pending wider societal debate and regulation.