Study suggests expanding the genetic alphabet may be easier than previously thought - A new study led by scientists at the Scripps Research Institute suggests that the replication process for DNA -- the genetic instructions for living organisms that is composed of four bases (C, G, A and T) -- is more open to unnatural letters than had previously been thought. An expanded "DNA alphabet" could carry more information than natural DNA, potentially coding for a much wider range of molecules and enabling a variety of powerful applications, from precise molecular probes and nanomachines to useful new life forms. Reference: 'KlenTaq polymerase replicates unnatural base pairs by inducing a Watson-Crick geometry,' F. E. Romesberg et al, Nature Chemical Biology (2012) doi:10.1038/nchembio.966