Gene Linked to Increased Risk of Alzheimer's Disease
Scientists are one step closer to understanding late-onset Alzheimer’s disease, the most common form of this devastating disease. Variations in a gene named MTHFD1L appear to impose a nearly twofold increased risk of Alzheimer’s disease on people who carry the altered gene.
Discovery of gene may improve Alzheimer’s treatment
Investigators from four institutions collaborated on the research and identified differences in the genetic sequences of the MTHFD1L gene in individuals with and without Alzheimer’s disease. According to Margaret A. Pericak-Vance, PhD, director of the John P. Hussman Institute for Human Genomics at the University of Miami Miller School of Medicine and head of the team, identification of this gene “is important because the gene is known to be involved in influencing the body’s levels of homocysteine, and high levels of homocysteine are a strong risk factor for late-onset Alzheimer’s disease.”
In a previous study conducted by scientists at Queen’s University Belfast and published in Stroke, it was reported that moderate elevations of homocysteine were associated with a nearly threefold increased risk for Alzheimer’s disease and a more than fivefold increased risk for stroke. Homocysteine is an amino acid believed to be toxic to blood vessels.
Dr. Pericak-Vance also pointed out that variations of the MTHFD1L gene have also been suggested to have a role in increasing the risk of coronary artery disease. “Since the function of blood vessels in the brain may affect Alzheimer’s disease, this finding may help us understand how homocysteine leels and blood vessel function in the brain affect Alzheimer’s disease,” she said.
The research team observed the variations in the gene throughout the human genomes of 2,269 individuals who had late-onset Alzheimer’s disease and 3,107 healthy controls. Joseph D. Buxbaum, PhD, department of psychiatry at Mount Sinai School of Medicine noted that their finding provides “unique insight into possible interactions between genetic and environmental risk factors that contribute to AD.”
New insights into prevention and treatment of Alzheimer’s disease are desperately needed. The latest statistics released by the Alzheimer’s Association show that about 5.3 million Americans have this form of dementia, and by 2030, the number of people aged 65 and older with Alzheimer’s is expected to reach 7.7 million, and between 11 and 16 million by 2050 unless medical breakthroughs find ways to stop or slow this disease.
This latest discovery of a gene variation that appears to increase the risk of the most common form of Alzheimer’s disease “will lead to a better understanding of what’s happening in Alzheimer’s disease, and how we can improve treatment,” added team member Jonathan L. Haines, PhD, Vanderbilt Center for Human Genetics Research at Vanderbilt University.
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