Scientists Discover New Alzheimer's Disease Risk Genes

April 4, 2011— -- Scientists have discovered five genes linked to an increased risk for late-onset Alzheimer's -- a finding that sheds light on the still mysterious disease and could lead to new predictive tests and treatments.

Two mammoth research teams -- one from the U.S., the other from Europe -- identified variations in the genes ABCA7, MS4A, CD2AP, CD33 and EPHA1 that are associated with an increased susceptibility to the disease. The results were published as two separate reports today in Nature Genetics.

"This is the culmination of years of work on Alzheimer's disease by a large number of scientists, yet it is just the beginning in defining how genes influence memory and intellectual function as we age," Gerard Schellenberg, leader of the University of Pennsylvania study, said in a statement.

The U.S. study, which was carried out by researchers from 44 universities and research institutions across the country, involved genetic analysis of more than 11,800 people with Alzheimer's disease and almost 11,000 elderly people who were "cognitively normal."

The discovery is an important step in a long journey toward new treatments for the neurodegenerative disease that impairs memory and cognition.

"We're all tremendously excited by our progress so far, but much remains to be done, both in understanding the genetics and in defining how these genes influence the disease process," Schellenberg said.

Alzheimer's disease is the leading cause of dementia and the sixth leading cause of death in the U.S., according to the Centers for Disease Control and Prevention. Although specific genetic mutations are known to cause the early onset form of the disease, the late onset form is thought to arise from a complex interaction of susceptibility genes and other risk factors.

"The present reports provide new information that fills in some of the important knowledge gaps in our understanding of the genetics of the common form of late-onset Alzheimer's disease," said Dr. Gary Small, director of the UCLA Center on Aging, who was not involved in the study.