Biomolecular researchers have been long accused of playing god, and, for a change, they may actually be on the verge of doing so. DNA is prodigious in its ability to encode genetic information, but scientists wonder if a code based on a four-letter alphabet is enough. Apparently not. Researchers in Japan have prepared “unnatural” DNA bases that can be incorporated into “natural” DNA. They do act unnaturally in vitro, forming base pairs via hydrophobic bonds, instead of the usual hydrogen bonds. What's more, enzymes involved in DNA metabolism can recognise and act on these unnatural bases as well (Nature Methods 2006;3:729-35).
Would human sexual organs lose their raison d'être if pleasure were removed from the equation? In raising this question, perhaps, was the peculiar case of a man who had two fully functional penises-a condition known as penile duplication or diphallus. The odds of this happening are 5.5 million to