Lytico-Bodig Disease - Research

Research

Some hypotheses as to the cause of the disease include genetics, cycad seeds, and ingested BMAA from the consumption of fruit bats. The actual cause of the disease is as mysterious as the vast manifestations of the disease itself.

• Genetics was first hypothesized due to the situation on Guam. Lytico-bodig was found in great numbers among members of the Chamorro community, so genetic factors were possible. It was the first to be disproved; only the older generation of Chamorro had the disease, and it had disappeared in one generation. Also, Chamorro who grew up outside of Guam had not developed the disease, and some non-Chamorro who moved to the island and followed the culture did develop it. Therefore, this hypothesis was quickly dropped
• Cycad seeds are a big part of the Chamorro lifestyle. They are ground to make a flour called fadang, and the flour is then used to make tortillas and dumplings. The flour is soaked and cleaned several times because the seed in its natural form is extremely toxic. One article described livestock that drank from the water of the first cleaning dropped dead instantly. Ample research on the cycad hypothesis found a component of the seeds, cycasin, was a potent toxin; it was discovered in the 1950s. As toxic as it was, it would not be the cause of the symptoms of lytico-bodig. However, another toxic substance was found in the seeds. In the 1960s, British biochemists found a substance called beta-N-methylamino-levoalanine or BMAA. Experiments were performed to test the toxicity; when monkeys were fed synthetic BMAA, they developed symptoms of ALS-PDC and thus of lytico-bodig. However, the treated flour was tested for BMAA, and was not found to contain sufficient quantities.
• Another theory was introduced by Paul Alan Cox and Oliver Sacks after examining aspects of the Chamorro diet. Fruit bats, which often ate cycad seeds, were a common food for the Chamorros. The bats bioaccumulate BMAA in their fat, and eating even a few bats would cause a dose of BMAA similar to levels that produced disease symptoms in the earlier animal models. Cox also observed decline in fruit bat consumption matched the decline in lytico-bodig. This hypothesis is still being investigated.

The actual disease could be eliminated before a cure is found, since only the older generation of people on Guam have it, and the cause has not yet been found.

Lytico-bodig is isolated to Guam which makes it an excellent opportunity to research neurodegenerative diseases. If a cure were found, it could lead to significant information on other diseases, such as Parkinson's and Alzheimers. Only time and future research will tell the outcome of the disease.