Study Finds Similar Gene Variations in African-American and Caucasian Alzheimer’s Patients
By Hook Law Center
In one of the first large studies on Alzheimer’s in African-Americans, researchers found the same gene variants that previous studies found in Caucasian Alzheimer’s patients. APoE4, a gene long known to correlate with higher Alzheimer’s risk in Caucasian people, was identified in a similar percentage of African-American patients as Caucasian patients. Another, ABCA7, was found at slightly higher rates in African-Americans with the disease.
In an editorial accompanying the publication of the research, Dr. Robert L. Nussbaum of the University of California, San Francisco, said that finding the genes in African-Americans supports theories that they contribute to susceptibility to Alzheimer’s.
The study analyzed data from 6,000 African-Americans over the age of 60. Approximately 2,000 had been diagnosed with Alzheimer’s disease.
Researchers determined that ABCA7 confers an 80 percent increase in the risk of Alzheimer’s in African-Americans, compared with a risk of 10 to 20 percent among whites. Even 80 percent is considered modest; a gene conferring significant risk would at least double the likelihood of a disease. And the gene is fairly uncommon even among African-American Alzheimer’s patients, leaving the cause of the disease mostly unexplained.
ABCA7 helps move cholesterol in and out of cells and is also suspected of influencing the development of heart disease. That may explain why many Alzheimer’s patients are diagnosed with cardiovascular disease and vice-versa.