At Jef Boeke’s lab, you can whiff an odor that seems out of place, as if they were baking bread here.   But he and his colleagues are cooking up something else altogether: yeast that works with chunks of man-made DNA. Scientists have long been able to make specific changes in the DNA code. Now, they’re taking the more radical step of starting over, and building redesigned life forms from scratch. Boeke, a researcher at New York University, directs an international team of

11 labs on four continents working to “rewrite” the yeast genome, following a detailed plan they published in March. Their work is part of a bold and controversial pursuit aimed at creating custom-made DNA codes to be inserted into living cells to change how they function, or even provide a treatment for diseases. It could also someday help give scientists the profound and unsettling ability to create entirely new organisms. The genome is the entire genetic code of a living thing. Learning how to make one from scratch, Boeke said, means “you really can construct something that’s completely new.” READ MORE