Occurrence of β-methylamino-l-alanine (BMAA) in ALS/PDC patients from Guam


Paul Alan Cox, Institute for Ethnobotany, National Tropical Botanical Garden, 3530 Papalina Road, Kalaheo, HI 96741, USA
Tel.: 801 375 6214
Fax: 801 373 3593
e-mail: paulcox@ntbg.org


We tested the brain tissues of the Chamorro people of Guam who died of amyotrophic lateral sclerosis/Parkinsonism dimentia complex (ALS/PDC) for the neurotoxin β-methylamino-l-alanine (BMAA). We used validated high-pressure liquid chromatography and liquid chromatography-mass spectrometry analyses to test well-characterized archival tissues of the superior frontal gyrus from eight Chamorros from Guam and a comparison group of 15 Canadians. BMAA was found as a free amino acid in 83% of Chamorro ALS/PDC patients (3–10 μg/g) as a protein-associated amino acid in 100% of the Chamorro individuals (149–1190 μg/g). Both forms of BMAA were also found at comparable levels in two Canadians who died of progressive neurodegenerative disease. BMAA, which is produced by cyanobacteria, may be associated with some cases of neurodegenerative disease.