Landmark Study Reveals 42 New Genes Associated with Increased Risk of Developing Alzheimer's Disease
Alzheimer's disease is a widespread illness that impacts roughly six million Americans across all ages. The prolific brain ailment is the subject of a multitude of studies ranging in size, but recently the largest study of genetic risk of Alzheimer's to date was conducted and uncovered an additional 42 genes connected to the development of the disease. "This is a landmark study in the field of Alzheimer's research and is the culmination of 30 years' work," study co-author Julie Williams, center director at the UK Dementia Research Institute at Cardiff University, said in a statement.
To obtain their findings, the researchers analyzed the genomes of 111,326 people diagnosed with Alzheimer's and compared those with genes from 677,663 cognitively healthy people. The genomes were provided by clinics in over 15 members of the European union, including Argentina, Australia, Brazil, Canada, Iceland, Nigeria, New Zealand, the United Kingdom, and the United States. In all, the global study identified 75 genes linked to an increase risk of developing Alzheimer's, 42 new and 33 already known genes.
Many of the newly identified genes are suspected to be pathways for the development of Alzheimer's disease. For example, some of the genes were associated with an immune regulator that's necessary to activate genes and prevent cell death in the body. Additionally, researchers found that a handful of the new genes may cause microglia—immune cells responsible for clearing away damaged neurons—to be less efficient, which may accelerate the disease. Genes associated with inflammation were another key pathway to Alzheimer's outlined in the study, as the body uses inflammation to kill off pathogens and remove damaged cells.
While lifestyle factors like smoking, exercise, and diet play a key role in our development of Alzheimer's, Williams says that 60 to 80 percent of disease risk is based on our genetics. For this reason Williams stresses the importance of seeking out the biological causes and developing essential treatments for the millions of people affected by the illness. Fortunately, this global study takes us one step closer to understanding what causes Alzheimer's. "Creating an extensive list of Alzheimer's disease risk genes is like having the edge pieces of a puzzle put together, and while this work doesn't give us the full picture, it provides a valuable framework for future developments," Susan Kohlhaas, director of research at Alzheimer's Research UK told CNN.