Life from scratch

In the summer of 2010, a team of scientists announced they had created a living cell whose entire genetic instruction manual was made by human technology. "We have a biological self-replicating organism whose parent was a computer file," one researcher said. "An email attachment, if you will." The cell, nicknamed Cynthia, was a world first—and it opened a door to a question that had nagged biologists for decades: what is the absolute minimum a cell needs to be alive?

The dream of a minimal cell

The effort was led by J. Craig Venter, the iconoclastic biologist who had just helped decode the human genome, and John Glass, a mycoplasma expert who joined what became the J. Craig Venter Institute (JCVI). Their target was the simplest possible organism—a cell with the smallest possible genome. In nature, some bacteria called mycoplasmas already have remarkably few genes (around 1,000, compared to 20,000–30,000 in humans). But the team wanted to go even further, down to the bare essentials.

The plan was to chemically synthesize a genome in the lab, edit it to remove nonessential genes, and then transplant it into a living cell to see if the cell would survive. This was a two-step problem. First, could they transplant a whole synthetic genome into a cell at all? Second, once they could, how many genes could they strip away before the cell died?