Artificial life takes slow step forward

Scientists are advancing slowly toward one of the most audacious goals humans have ever set for themselves: creating artificial life.

They've already taken some steps needed to construct a simple, single-celled organism that's capable of evolving and reproducing itself – basic requirements for life.

“We have made considerable progress,” said Jack Szostak, an artificial life investigator at the Howard Hughes Medical Institute in Chevy Chase, Md. “Any prediction like this is just a guess, but I'm hoping we'll have a synthetic cell in under 10 years.”

Such a cell would be “unrelated to any existing life form on Earth,” Szostak said.

Other experts, however, said it might take decades or centuries before scientists would be able to “create life from scratch,” as the quest is colloquially known.

Meanwhile, researchers are laboriously modifying and assembling existing biological molecules to construct synthetic cells with some – but far from all – of the attributes of living creatures.

So far, what they're doing is more like copying nature's tricks than creating new life forms in the lab, with all the philosophical, social and religious issues that such a feat would imply.

“Creating artificial life is very different from reproducing what existed already in nature,” said Eckhard Wimmer, a microbiologist at Stony Brook University on Long Island, NY. “That (artificial life) may be possible in the future, but this future may be hundreds of years away.”

According to Szostak, a living cell has two essential needs: First, a set of genes that contain instructions for it to eat, grow, divide and reproduce, and second, a surrounding membrane or wall that separates its contents from the outside world but allows nutrients to enter.

In June, Szostak announced that his lab had constructed a model “protocell,” a synthetic membrane enclosing a copy of an existing strand of genetic material. His team now is trying to synthesize the other half of the puzzle: some form of artificial DNA.

“We've made good progress on the cell membrane, leaving the genetic material as the major challenge,” Szostak said.