Experts say biology breakthrough has long path

Craig Venter's team has managed to insert a whole bacterium chromosome into another type of bacteria Keystone

Swiss researchers say American work on an artificial cell is a technological breakthrough, but that it could be many more years before any benefits become apparent.

United States genome pioneer Craig Venter and his team have reported a major step forward in their attempts to make synthetic life, creating an artificial genome and using it to bring a bacterium back to life.

The scientists hope to use their stripped-down version of a bacterium to learn how to engineer custom-made microbes.

“This is the first synthetic cell that’s been made,” said Venter. “This is the first self-replicating species that we have had on the planet whose parent is a computer.”

Other members of his research team said later they had only taken “baby steps” toward the goal of starting with a digital file and custom-making an organism.

According to Sven Panke, a Basel-based professor of bioprocess engineering at the Swiss Federal Institute of Technology Zurich (ETHZ), Venter’s team has managed a breakthrough.

“The whole process published over the past few years opens up the scope of what we can do in microbiology and biotechnology,” he told swissinfo.ch.

“Venter has synthesised a whole chromosome and found a way to implant it in a bacterium, which is a heroic task in terms of the work and the difficulties to overcome.”

No life yet

Panke says that Venter has not created life though, but has replicated an existing chromosome, building it step by step.

Reporting in this week’s edition of the journal Science, the research team said it had worked with a synthetic version of the DNA from a small bacterium transplanted into another germ, which had most of its insides removed.

It took a long time to figure out how to make an artificial chromosome with artificial genetic sequences. The researchers, who have spent 15 years and $40 million (SFr46 million) so far, then had to understand how to transfer this into another bacterium and let it replicate.

“In a sense, it’s like they exchanged the software, but not the hardware surrounding it,” said Panke.

Venter has said that he would like to try to make bacteria to produce fuel or for making better vaccines or even to design algae that can vacuum up carbon dioxide from the atmosphere.

“This becomes a very powerful tool for trying to design what we want biology to do,” Venter said at a news conference.

More work

So far the result is a functioning copy of an existing chromosome. The difficulty now, warns Panke, is introducing new elements into a chromosome to create a novel and reliable functionality, an issue that Venter has not yet addressed.

There are no guarantees either that a reprogrammed cell would do what it was designed for.

“Biological systems evolve,” said Panke. “Codes that are programmed tend change over time.”

“Cells are also terribly complex systems,” he added, “there are thousands of genes and proteins all interacting. To fully understand and predict how this interaction will take place is terribly difficult.”

Venter said the team consulted many experts in ethics before it started. The White House was briefed because of the security implications – the technique might be used to synthesize biological weapons, for instance.

Risks debate

US President Barack Obama has asked the Presidential Commission for the Study of Bioethical Issues to look at the issue, weighing both the benefits and the risks.

Panke says the dangers of the technology are minimal at this stage.

“We have been discussing safety issues since the beginning of the decade,” he told swissinfo.ch. “For the time being, synthetic biology does not pose any significant problems.”

Bernard Baertschi, an ethicist at Geneva University, says how this type of development is accepted will depend also on people’s conception of life and how it should be treated.

But he adds that the debate will focus on risk factors.

“Some people think that tinkering with life forms is fundamentally immoral, but as this is not a widely accepted point of view among the general public, they will prefer to discuss the risks,” he told swissinfo.ch.

“The problem is that these same people will be against this technology no matter how small the risks are,” he added.

Scott Capper, swissinfo.ch

Craig Venter

John Craig Venter is an American biologist and entrepreneur, most famous for his role in being one of the first to sequence the human genome.

Venter founded the J. Craig Venter Institute, a not-for-profit, research and support organisation with more than 400 scientists and staff.

Venter also founded Celera Genomics in 1998, a for-profit company, to sequence the human genome using new tools and techniques he and his team developed, competing with the international Human Genome Project (HGP).

In 2000, Venter and the US National Institutes of Health and Public Genome Project jointly made the announcement of the mapping of the human genome in 2000, a full three years ahead of the expected end of the HGP.

In 2007, a team published the first complete (six-billion-letter) genome of an individual human, in this case Venter’s own DNA sequence.

Some of the sequences in Venter’s genome are associated with wet earwax, an increased risk of antisocial behaviour, Alzheimer’s disease and cardiovascular problems.

Synthetic biology

Synthetic biology studies how to build artificial biological systems.

It is an engineering application of biological science, rather than an attempt to do more science.

It often focuses on ways of taking parts of natural biological systems, characterising and simplifying them, and using them as a component of a highly unnatural, engineered, biological system.

Biologists are interested in synthetic biology because it provides a complementary perspective from which to consider, analyse, and understand the living world.