The exact cause of Azheimer’s disease is still unknown; however, research shows a higher prevalence among those with a family history of it, so here we explore how genetics affect Alzheimer’s disease.
What causes Alzheimer’s disease?
Alzheimer’s disease (AD) is the most common cause of dementia, which is characterized by impaired memory, inability to perform routine daily tasks and behavioral changes. Though the exact cause is still unknown, the incidence of AD has been noted to increase with aging.
The prevalence of dementia is estimated at 25 million people globally and AD accounts for two out of three cases. It may be categorized as familial (inherited) or sporadic (new onset) and the vast majority of cases of have no known cause.
Some authors have also reported early onset AD in patients with Down’s syndrome that is attributable to alterations in amyloid precursor protein (APP) genes in chromosome 21. APP genetic mutation has also been noted in individuals with hereditary AD.
What changes occur in the brain in AD?
Previous studies have demonstrated an increased amount of plaques known as neurofibrillary tangles in the brains of people with AD.
Do genetics affect Alzheimer’s disease?
The genetic mechanisms of AD have not been well elucidated. However, genetic studies have identified an autosomal dominant inheritance pattern in AD and APP and presenilin (PSEN) genes among individuals with increased amounts of amyloid plaques in the brain, and thus the association with the pathogenesis of AD.
What is the cure for AD?
Currently there is no known cure, or treatment options that delay the onset or slow the progression of AD.
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Last reviewed 03/Jan/2017