Adapted from the National Institute on Aging
Until recently, only one of the approximately 30,000 genes in the human genome has been linked to risk of late-onset Alzheimer's disease (AD). Now, a new NIH-supported study in the Nov. 19, 2007, issue of NeuroReport (now online) used a publicly shared genome dataset to strongly support findings that variation in the sequence of the SORL1 gene may be a second risk factor gene for late-onset disease. Identifying the genes involved in AD ultimately may help determine who may be at greater risk and enable researchers to zero in on pathways to develop new treatments.
The National Institute on Aging (NIA), part of the National Institutes of Health (NIH), funded the study, along with the Canadian Institutes of Health Research and a number of private foundations in the U.S., Canada and Japan.
Three mutated genes—amyloid precursor protein (APP) and the presenilins (PS1 and PS2) —have been shown to cause rare, early-onset, familial forms of the disease which mostly occur in middle age. A gene variant—apolipoprotein e4 (APO-e4)—was the first confirmed risk factor for the common form of late-onset AD, which typically occurs after age 65.