While much has been made of the Apolipoprotein E-e4 (APOE-e4) as a genetic marker for Alzheimer's, scientists today announced they've discovered 11 new genes that may be tied to the disease in aging populations.
Researchers' findings were based on 74,076 brain scans belonging to older men and women in 15 countries. The study was published over the weekend in the journal Nature Genetics.
Prior to this study, only 11 gene variants had been linked to late-onset Alzheimer's disease, including APOE-e4, which appeared to have the strongest impact on risk.
Now, with the latest research, scientists have doubled the known gene variants linked to the disease and belive there is something in the immune response that may cause someone to develop Alzheimer's.
In particular, researchers honed in on varient HLA-DRB5/DRB1, which resides in an area of the brain that controls how white blood cells interact. These cells are linked to immune systems. This area of the brain has also been connected with multiple sclerosis and Parkinson's disease.
"Interestingly, we found that several of these newly identified genes are implicated in a number of pathways," Gerard Schellenberg, professor of pathology and laboratory medicine at the University of Pennsylvania School of Medicine in Philadelphia, said in a news release. "Alzheimer's is a complex disorder, and more study is needed to determine the relative role each of these genetic factors may play."