When any of these genes is altered, large amounts of a toxic protein fragment called amyloid beta peptide are produced in the brain. This peptide can build up in the brain to form clumps called amyloid plaques , which are characteristic of Alzheimer disease.
A buildup of toxic amyloid beta peptide and amyloid plaques may lead to the death of nerve cells and the progressive signs and symptoms of this disorder. Other cases of early-onset Alzheimer disease may be associated with changes in different genes, some of which have not been identified. Some evidence indicates that people with Down syndrome have an increased risk of developing Alzheimer disease. Down syndrome , a condition characterized by intellectual disability and other health problems, occurs when a person is born with an extra copy of chromosome 21 in each cell.
As a result, people with Down syndrome have three copies of many genes in each cell, including the APP gene, instead of the usual two copies.
Although the connection between Down syndrome and Alzheimer disease is unclear, the production of excess amyloid beta peptide in cells may account for the increased risk. People with Down syndrome account for less than 1 percent of all cases of Alzheimer disease. This type of Alzheimer disease is not inherited. The causes of late-onset Alzheimer disease are less clear. The late-onset form does not clearly run in families, although clusters of cases have been reported in some families.
This disorder is probably related to variations in one or more genes in combination with lifestyle and environmental factors. A gene called APOE has been studied extensively as a risk factor for the disease. In particular, a variant of this gene called the e4 allele seems to increase an individual's risk for developing late-onset Alzheimer disease. Many more genes have been associated with Alzheimer disease , and researchers are investigating the role that additional genes may play in Alzheimer disease risk.
Early-onset familial Alzheimer disease is inherited in an autosomal dominant pattern , which means one copy of an altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person inherits the altered gene from one affected parent. The inheritance pattern of late-onset Alzheimer disease is uncertain. People who inherit one copy of the APOE e4 allele have an increased chance of developing the disease; those who inherit two copies of the allele are at even greater risk. It is important to note that people with the APOE e4 allele inherit an increased risk of developing Alzheimer disease , not the disease itself.
Not all people with Alzheimer disease have the e4 allele, and not all people who have the e4 allele will develop the disease.
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Ertekin-Taner N. They may struggle with vocabulary, have problems finding the right word or call things by the wrong name e. Sometimes having trouble finding the right word. A person with Alzheimer's disease may put things in unusual places. They may lose things and be unable to go back over their steps to find them again. Sometimes, they may accuse others of stealing. This may occur more frequently over time. Misplacing things from time to time and retracing steps to find them.
People with Alzheimer's may experience changes in judgment or decision-making. For example, they may use poor judgment when dealing with money, giving large amounts to telemarketers. They may pay less attention to grooming or keeping themselves clean. Making a bad decision once in a while. A person with Alzheimer's may start to remove themselves from hobbies, social activities, work projects or sports. They may have trouble keeping up with a favorite sports team or remembering how to complete a favorite hobby. Sometimes feeling weary of work, family and social obligations.
The mood and personalities of people with Alzheimer's can change. They can become confused, suspicious, depressed, fearful or anxious. They may be easily upset at home, at work, with friends or in places where they are out of their comfort zone. Developing very specific ways of doing things and becoming irritable when a routine is disrupted.
Get checked. Early detection matters. If you notice any of the 10 Warning Signs of Alzheimer's in yourself or someone you know, don't ignore them. Schedule an appointment with your doctor. With early detection, you can explore treatments that may provide some relief of symptoms and help you maintain a level of independence longer, as well as increase your chances of participating in clinical drug trials that help advance research.
As it turns out, we weren't so far from the truth about old timers getting a disease in which they lose their minds. Although early-onset AD is. The term "old timer's disease" is commonly used by uneducated people who aren 't aware that the disease is actually called, "alzheimer's disease." People that.
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Memory loss that disrupts daily life may be a symptom of Alzheimer's or other dementia.