or alleles (Apo E 2,3,4) and each person has a combination of two of the three. Thus an individual can have any one of the following combinations: Apo E 2/2, 3/3, 4/4, 2/3, 3/4 or 2/4. Researchers have found a relationship between the number of copies of the 4 allele and the person's probability of developing the disease. For example a 75 year old individual with the Apo E 4 genotype has approximately a 20% chance of remaining normal; Apo E 3/4 or 2/4, 40%; 2/2, 3/3 or 2/3, a 75% chance (Institute, 1996, p. 6). For many years, scientists believed that aluminum was at the root of Alzheimers disease. High levels of aluminum were detected in the areas surrounding the beta-amyloid plaques associated with neural atrophy (Pollen, 1990, p.77). Recently however, this theory has been abandoned. Scientists concluded that the build-up of aluminum was a direct result of the wrongful use of a particular test agent employed in the studies (Brown, 1992, p.6).Some of the current pursuits of research are in the areas of viral infection, malfunction of the immune system, and chemical imbalances. One of the hardest theories to disprove is that Alzheimers disease is the result of a slow acting virus present at birth (Carlton, 1996, p.13). Others believe that Alzheimers disease is an immune system disorder. Support for this theory comes from the presence of beta-amyloid plaques identical to those found in Alzheimer-diseased brains in the post-mortem examinations of immuno-deficiency disease victims (Alzheimer's, 1996, p.22). The detection of lower neurotransmitter substances such as acetylcholine, serotonin, norepinephrine and somatostatin in Alzheimers sufferers forms the basis of another theory that says Alzheimers disease is brought on by a chemical imbalance in the brain. Treatment of patients with drugs that block the breakdown of neurotransmitter substances in the brain have been met with limited success (Brassard, 1993, p.16). ...
