It has been 50 years since scientists first created DNA in a test tube, stitching ordinary chemical ingredients together to make life’s most extraordinary molecule. Until recently, however, even the most sophisticated laboratories could make only small snippets of DNA — an extra gene or two to be inserted into corn plants, for example, to help the plants ward off insects or tolerate drought. Now researchers are poised to cross a dramatic barrier: the creation of life forms driven by completely artificial DNA. Scientists in Maryland have already built the world’s first entirely handcrafted chromosome — a large looping strand of DNA made from scratch in a laboratory, containing all the instructions a microbe needs to live and reproduce. In the coming year, they hope to transplant it into a cell, where it is expected to ‘boot itself up,’ like software downloaded from the Internet, and cajole the waiting cell to do its bidding. And while the first synthetic chromosome is a plagiarized version of a natural one, others that code for life forms that have never existed before are already under construction. The cobbling together of life from synthetic DNA, scientists and philosophers agree, will […]