In the slender, microscopic form of C. Elegans -- a roundworm so small it takes just three days to develop into a full-grown adult -- scientists may have stumbled onto a clue to the mystery of why diseases like Alzheimer's suddenly cause massive numbers of brain cells to die.

In the current issue of the journal Nature, Columbia University researchers Martin Chalfie and Eve Wolinsky report that after studying a similar wave of cell death in the C. Elegans roundworm they have identified three defective genes as the culprit.

Roundworms are not humans, of course. But they are the best surrogate researchers have, because the kind of close observation and targeted research needed to find the defective genes are not possible on anything more complicated than a roundworm. There are also good reasons to believe that, on a molecular level, C. Elegans may serve a very useful analogy for what goes on in a human brain. For example, humans and the worm share many of the same neurotransmitters as well as many similiar neurological genes and proteins.

Armed with a profile of the defective genes, the two scientists hope that eventually they will be able to look for similar defective genes in humans and perhaps design diagnostic tests to detect their presence and identify those at risk for neurodegenerative diseases like Alzheimer's or Huntington's diseases.

In the meantime, the roundworms will be used as models to better understand neurodegenerative diseases and test new therapies that might help prevent cell death.