Dementia is a neurological disorder where those affected suffer from a loss of cognitive ability. It is most common in older generations; however, it can occur before the age of 65 in what is known as early onset dementia. Alzheimer’s disease is the most common form of dementia. About 15.9 million Americans suffer from the disease and it is the sixth leading cause of death in the United States. While other leading causes of death can be prevented through medications and altering daily routines, there is no cure for Alzheimer’s. Alzheimer’s is a degenerative disease caused by both genetic factors and more controversially, zinc and aluminum. It is treated with medicines designed to slow down the nerve damage in the brain and prevent further memory loss. Caregivers also help to care for the patients.
Typical characteristics of Alzheimer’s disease include memory loss, confusion with time or place and a difficulty performing standard tasks at home or in the office. Those with the disease have to rely on friends, family, and aides to help them remember who they are and where they are. People affected also transport themselves back in time because of their inability to keep track of time. Difficulty identifying spatial and visual relationships, and showing problems in both writing and speaking are also signs of Alzheimer’s.
Multiple things cause these symptoms of Alzheimer’s, although some theories are more concrete than others. There is little doubt by scientists that genetics play a huge role. Someone who has family suffering from Alzheimer’s is 3.5 times as likely to develop the disease. The passing down of these traits is a common characteristic of genetic influence in a disease.
There are three specific genes in human DNA that have been linked to Alzheimer’s. They are the beta-Amyloid precursor protein (APP), presenilin 1 (PS1), and presenilin 2 (PS2). All of these are passed down from a carrier to their offspring. Mutations in these genes cause their recipients to develop early onset Alzheimer’s.
In the APP gene of Alzheimer’s patients, located on chromosome 21, the mutations cause the brain to produce excess amounts of a protein called beta-amyloid. Though there are different variations of the gene, all mutations occur on the same region of the gene. The amyloid plaque buildup in the brain is a typical characteristic of Alzheimer’s.
PS1 and PS2 are very similar in structure, but PS1 mutations, which occur in nearly half of Alzheimer’s patients, are by far more common than PS2 mutations, which are very rarely documented. PS1 is caused by a mutation on chromosome 14 while PS2 is caused by a mutation found on chromosome one. PS2 mutations are also not necessarily the cause of Alzheimer’s. Some people who have the mutation never develop the disease.
Other genes that are inherited may not be the direct cause of Alzheimer’s, but may influence the development of the disease. For example, Apolipoprotein E (APOE), which found on chromosome...