Scientists have discovered four new genes associated with an increased risk of late-onset Alzheimer’s disease. The findings will help researchers explore new therapies and allow doctors to better predict who will develop the disease.

The Alzheimer’s Disease Genetics Consortium conducted the research in collaboration with 44 different universities and research centers, including Northwestern University. The study, published in the current issue of Nature Genetics, is the largest of its kind.

The results of the study double the number of genes currently known to contribute to Alzheimer’s. Of the four genes previously confirmed, the gene for apolopoprotein E-e4, called APOE-e4, has the largest effect on risk. The genes discovered in this study are called MS4A, CD2AP, CD33 and EPHA1.

Alzheimer’s disease affects more than 13 percent of people age 65 and older and nearly half of those 85 and older. Women are more likely than men to have this common form of dementia, possibly because women have a higher life expectancy.

Although there are currently no effective treatments or preventative measures for Alzheimer’s, the ability to predict who will develop the disease will be important when preventative steps become available. The findings will also help researchers identify the disease’s earliest stages and understand the events leading to brain damage. Alzheimer’s is associated with the destruction of large parts of the brain and is characterized by the loss of cognitive abilities, including memory loss and intellectual decline.