The CAG repeat codes glutamine, a precourser to glutamate. Glutamate dehydrogenase is a mitochondrial enzyme that catalyzes the oxidation of glutamate to ammonia. It is not known if this is related to any apoptotic pathway. Maybe there is a connection to 3NPA, a great for science but bad for mice and primates mitrochondrial toxin.

It is interesting that a couple of non-aromic flavor agents that are chemically like glutamate can cause neurological defects. I suspect it is best that HD patients avoid these compounds. --Jerry 11/08/98

Aspartame is marketed under the trade names of "Equal", "Nutrasweet", "Spoonful" and "Equal Measure". Reports indicate that it is consumed by more people than any other synthetic product in history. [1] In 1992, 14 million pounds (6.4 million kilograms) were consumed.

• Contained in : Antibiotic syrups, chewable and effervescent vitamins, foods of all description, diet drinks, lipstick and many unlabeled products. There are no restrictions on its use in foodstuffs.
• Composition: Methyl Alcohol (10% by weight), aspartate and phenylalanine.
• Decomposes to: Formaldehyde & Formic Acid.
• Relatives: Monosodium Glutamate (MSG), Aspartates and glutamates differ by one methyl group and have similar undesirable effects. [2]

Toxic Effects:

Aspartates and glutamates are both excitatory amino acids. When excessive amounts of these are present in the brain they act as a neurotoxin destroying brain cells. The phenylalanine. component, when combined with the aspartic acid from the aspartate and the methyl alcohol, can deplete serotonin in the brain. High levels of phenylalanine. are associated with abnormal brain function and brain damage. Levels may reach 30-40 times normal in certain susceptible individuals producing Phenylketonuria, even in adults. Medium to high doses in monkeys produced grand mal seizures in all test animals within 218 days.

Symptomatology:

Memory loss, depression and irritability, tinnitus, flicker vertigo , flicker-induced epileptic activity, seizures, gradual loss of vision, dizziness, increased appetite. Possibly also peripheral neuropathy, joint pain. Brain cell damage may result in the symptoms of Alzheimer's and Huntington's Chorea.
 
[1]. Mullarky, B.A. & Newman, A.V. "The Hidden Effects of Aspartame", Informed Consent Sept/Oct 1994 p. 35-39.
[2]. Letter to Barbara Mullarky from Ralph Dawson Jr., Ph.D., Assistant Professor, University of Florida Department of Pharmacodynamics (January 29, 1988).