Alzheimer’s Disease Familial
Alzheimer's Disease Familial
Type of disease: Rare conditions
Alzheimer’s disease, familial is a progressive condition of the brain that affects memory, thinking, and behavior. While Alzheimer’s disease is not always genetic, familial Alzheimer’s disease has a specific genetic marker that runs in the family and is passed down through generations (inherited).
So far, three genes have been identified to cause familial Alzheimer’s disease: presenilin-1 (PS1), presenilin-2 (PS2) and amyloid precursor protein (APP). Changes in these genes (mutations) lead to two abnormal protein structures (“plaques” which are protein deposits and “tangles” which are twisted protein fibers) in the brain tissue along with the loss of connection between nerve cells in the brain. These changes cause the brain cells to lose normal function. Because these changed genes are inherited, familial Alzheimer’s disease may occur earlier than the traditional “late onset” disease (65 or older). Typically, familial Alzheimer’s disease onsets in one’s 30’s, 40’s or 50’s, and rarely sooner.
Symptoms of familial Alzheimer’s are similar to those of non-familial Alzheimer’s. These include loss of memory, behavioral changes, mood swings, disorientation, confusion, and unnecessary suspicion of family or others over a period of several years. Eventually symptoms progress to an inability to care for him or herself, to eat, or to speak. Diagnosis of this condition is made by examining family history and genetic testing. Almost all individuals with early onset familial Alzheimer’s have a parent who had the disease (assuming they lived long enough to develop symptoms). Siblings and children of an affected person likely each have a 50% chance of also developing the condition as well.
There is currently no cure for familial Alzheimer’s disease, but medications may help slow the progression, manage the symptoms and improve quality of life. Talk to your doctor or a geneticist if you have a family history of Alzheimer’s disease.