Researchers studying Alzheimer’s disease genes discovered a new gene called MGMT that increases the risk of this common dementia in women.
“This is one of the few, if not the strongest, associations of a genetic risk factor for Alzheimer’s disease that is specific to women,” said Lindsay Farrer, co-senior study author and chief of biomedical genetics at Boston University School of Medicine.
A team from the University of Chicago and Boston University School of Medicine looked for genetic links using two unrelated datasets and different methods for the new study.
One dataset came from a large family of Hutterites, a central European group known for its isolated culture and small gene pool, which has made it a popular focus for researchers studying genetic determinants of disease. In this data, all of the people studied for Alzheimer’s were women.
The researchers also examined genetic data from a group of 10,340 women who lacked APOE4. This gene, a well-known Alzheimer’s risk factor, is carried by approximately 60% of people of European ancestry and approximately 26% of the general population.
The new gene MGMT was found to be significantly associated with the development of Alzheimer’s disease in both sets of data.
“This finding is especially robust because it was discovered independently in two distinct populations using different approaches,” Farrer explained. “While the finding in the large dataset was most pronounced in women who did not have APOE4, the Hutterite sample was too small to evaluate this pattern with any certainty.”
Alzheimer’s disease is the leading cause of dementia, affecting over 5.8 million people in the United States.
“This study demonstrated the importance of founder populations for genetic mapping studies of diseases like Alzheimer’s,” said Carole Ober, chairwoman of human genetics at the University of Chicago and co-senior study author.
More research is needed to understand why MGMT influences Alzheimer’s risk in women. The study’s authors emphasized the importance of looking for risk factors that are specific to one gender.
The findings were published on June 30 in Alzheimer’s & Dementia: The Alzheimer’s Association Journal.
