Guam's Flying Fox Bat: A Deadly Delicacy?

Scientists have long tried to learn why the Chamorro people of Guam develop a brain disorder called ALS-PDC -- closely linked to Parkinson's, Alzheimer's, and Lou Gehrig's disease -- at 50 to 100 times the incidence elsewhere. The answer could lie in the diet of the flying fox bat, say researchers led by Paul Alan Cox of the National Tropical Botanical Garden Institute. Their discovery may shed light on the development of some neurodegenerative diseases.

Guam's flying fox bats are a prized food of the Chamorro. And the bats are known to eat cycad seeds, which contain a neurotoxin called BMAA. The amount of toxin in the seeds is too small to be dangerous to humans. But the researchers found that BMAA accumulates and becomes more potent as it moves up the food chain -- a process called biomagnification. When autopsies were performed on Chamorro patients who died of ALS-PDC, high concentrations of BMAA were found in their brains.