The 1990s may well be remembered in biology as the decade of the gene, culminating in the completion of the Human Genome Project's working draft. And the next big thing in medicine may be the study of the proteins coded for by all those genes (see "The Proteomics Payoff"). But even as doctors and drug companies struggle to interpret and exploit the recent explosion of data on genes and proteins, yet another field of biology is waiting to break out: glycomics. This emerging discipline seeks to do for sugars and carbohydrates what genomics and proteomics have done for genes and proteins-move them into the mainstream of biomedical research and drug discovery.

For years, carbohydrates were one of the least glamorous subjects in biochemistry research. At best, scientists thought, these molecules created structure (in the cell walls of plants, for example) or were used to store energy (think potato); at worst, they hindered the study of important biological molecules like DNA and proteins. However, a very different portrait of sugars is gradually emerging. Biologists are finding that minor differences in sugar structures can have a huge impact on biological functions; in fact, sugars are involved in everything from embryonic development to regulation of the immune system. "Sugars are everywhere, in all organisms," says David Zopf, a vice president at Horsham, PA-based Neose Technologies, one of a number of research groups and companies working to exploit glycomics.