Heralding a potential new era in biology, scientists for the first time have created a synthetic cell, completely controlled by man-made genetic instructions, researchers at the private J. Craig Venter Institute announced Thursday.

"We call it the first synthetic cell," said genomics pioneer Craig Venter, who oversaw the project. "These are very much real cells."

Created at a cost of $40 million, this experimental one-cell organism, which can reproduce, opens the way to the manipulation of life on a previously unattainable scale, several researchers and ethics experts said. Scientists have been altering DNA piecemeal for a generation, producing a menagerie of genetically engineered plants and animals. But the ability to craft an entire organism offers a new power over life, they said.

The development, documented in the peer-reviewed journal Science, may stir anew nagging questions of ethics, law and public safety about artificial life that biomedical experts have been debating for more than a decade.