Scientists Create Stripped-Down Organism With Smallest Genome

One synthetic organism that has only the fundamental essentials with the fewest genes required to survive has been created by scientists. This is a remarkable achievement at the microscopic level, that may give some insights into the very essence of life.

J. Craig Venter, the genome research pioneer, labelled  the cell as the "most simple of all organisms." Even as the human genome has more than 20,000 genes, this fundamental organism has just 473.

"This study is definitely trying to understand a minimal basis of life," said Venter. But the function of nearly a third of the organism's function is still not clear, in spite of more than five years of hard work.

It would yield practical applications in creating new medicines, such as biochemicals, biofuels and in agriculture.

"Our long-term vision has been to design and build synthetic organisms on demand where you can add in specific functions and predict what the outcome is going to be," said Daniel Gibson, vice president for DNA technologies at Synthetic Genomics Inc, the company handling commercial applications from the research.

"I think it's the start of a new era," Venter added. He had been instrumental in mapping the human genome in 2001 and created the first synthetic cell in 2010 with the same team that undertook the research.

The team created a bacterial organism with a manmade genome, showing that genomes can be "designed on a computer, made in a laboratory and transplanted into a cell", creating a new organism that can replicate itself.

They then set out to remove unessential genes, using the fewest needed by the organism to live and reproduce.

At first, "every one of our designs failed" as they took out too many genes, Venter said.

"Life is much more like a symphony orchestra than a piccolo player. And we're applying the same philosophy now to our analysis of the human genome, where we're finding most human conditions are affected by variations across the entire genome" rather than a single gene, Venter said.

The environmental group Friends of the Earth expressed concern about the research, citing the lack of government regulations specific to synthetic biology and gene editing technologies.

"Living organisms like bacteria are not machines to be rewired," said Dana Perls, an official of the group. "Not even the scientists know the biological function of 149 of these genes, which raises safety concerns. If we don't fully understand the science, it is more difficult to manage biosafety concerns."