ALS is a universally fatal neurodegenerative condition that causes weakness leading to paralysis and death. Life expectancy is 2-5 years. The cause is unknown and there is no effective treatment. Previous research has shown that on autopsy, ALS patients are found to have increased levels of the amino acid glutamate accumulated in the brain and spinal cord. This increase is thought to be caused by a decrease in the glutamate transporter which normally "cleans up" glutamate from the cells.