Exploiting biology’s own chemical toolbox, researchers have developed a new technique that will allow them to modify specific sequences within a DNA molecule. The approach will not only help reveal the impact of biochemical alterations to DNA, but could have far-reaching implications for DNA-based medical diagnosis and nanobiotechnology. Combining chemistry with biotechnology, Saulius Klimasauskas, a Howard Hughes Medical Institute (HHMI) international research scholar at the Institute of Biotechnology in Vilnius, Lithuania, and chemists at the Institute of Organic Chemistry in Aachen, Germany, have harnessed a group of essential enzymes to add various chemical groups to DNA, thereby altering its function. The work was published in an early online publication on November 27, 2005 in Nature Chemical Biology.