The genetics of Alzheimer's disease

Abstract

A number of studies have determined a major role for genetic factors in the development of early onset familial Alzheimer's Disease (AD). These include the findings of rare, largely highly penetrant, autosomal dominant mutations in the genes coding for amyloid precursor protein, presenilin-1 and presenilin-2. In contrast, late onset AD, defined as age of onset at or after 65 years, is a complex disorder with a multi-factorial aetiology of variable genetic penetrance. To date, although a number of other candidates have been proposed, the clearest genetic risk factor associated with late onset AD remains the common ε4 polymorphism of apolipoprotein E (ApoE). The identification of new genetic risk factors for late onset AD is likely to depend upon a combination of both linkage and association studies.