New submitter dunnomattic writes: "Researchers at New York University School of Medicine have achieved a milestone in synthetic biology. A fully synthetic yeast chromosome, dubbed 'synIII,' has successfully replaced chromosome 3 of multiple living yeast cells. The researchers pieced together over 250,000 nucleotide bases to accomplish this feat. Dr. Jef Boeke, the lead author of the study, says, 'not only can we make designer changes on a computer, but we can make hundreds of changes through a chromosome and we can put that chromosome into yeast and have a yeast that looks, smells and behaves like a regular yeast, but this yeast is endowed with special properties that normal yeasts don't have.' Work is underway (abstract) to synthesize the remaining 15 chromosomes."