Jackson's and Emilia's Page. Yup.


Where on Chromosome is Problem?

Alzheimer's disease is caused by any one of a number of different single-gene mutations on chromosomes 21, 14, and 1. Each of these mutations causes abnormal proteins to be formed. Mutations on chromosome 21 cause the formation of abnormal amyloid precursor protein (APP). A mutation on chromosome 14 causes abnormal presenilin 1 to be made, and a mutation on chromosome 1 leads to abnormal presenilin 2.

What Is the Problem?

People with Alzheimer's will experience a gradual loss of memory and ability to think clearly over time. Alzheimer's disease can cause dementia- the loss of cognitive function (thinking, remembering, reasoning) and deterioration of behavioral abilities to the extent where it interferes with a person's daily life and activities. As Alzheimer's disease progresses, neurofibrillary tangles spread throughout the brain. By the time the disease has reached its final stage, damage is significant and brain tissue has shrunk dramatically. During the preclinical stages of Alzheimer's, there are no symptoms but toxic changes are taking place in the brain. Abnormal protein deposits form plaques and tangles throughout the brain which causes neurons to begin to work less efficiently and eventually the neurons die. The disease spreads to the hippocampus which is where the memory loss begins.

What is the Prognosis?

Alzheimer's is a progressive disease, where dementia symptoms gradually worsen over a number of years. In its early stages, memory loss is mild, but with late-stage Alzheimer's, individuals lose the ability to carry on a conversation and respond to their environment. Alzheimer's is the sixth leading cause of death in the United States. Those with Alzheimer's live an average of eight years after their symptoms become noticeable to others, but survival can range from four to 20 years, depending on age and other health conditions.

Cite Your Sources

What is Alzheimer's?
Alzheimer's Disease Fact Sheet