European researchers have found three new genes linked to an above-normal risk of developing Alzheimer's disease, according to a report in the Washington Post. Cumulatively, the three genes contribute about 22% of the overall risk of developing the disorder, the researchers reported in the journal Nature Genetics.
The most important gene previously linked to Alzheimer's is a mutation in the gene coding for apolipoprotein E or APOE, which leads to the overproduction of amyloid protein in the brain, damaging nerve cells. The normal function of the new genes appears to be shepherding excess amyloid protein out of brain cells. When they malfunction, the amyloid builds up faster.
The discovery has little immediate practical benefit. It cannot be used to screen for an increased risk of the disorder and it most likely does not present any therapeutic targets. But every little bit learned about the disorder contributes to long-term efforts to develop new preventive measures and therapies. The urgency of the search is accentuated by the prediction that at least 120 million people worldwide will suffer from Alzheimer's by 2050. There are currently no effective treatments for it--only drugs that can delay its effects briefly.
-- Thomas H. Maugh II