Researchers led by Dr. Paul Thompson, a UCLA professor of neurology, conducted brain scans on 398 young, healthy people ages 20 to 30. Those participants who carried a particular gene mutation that is known to raise the risk of Alzheimer’s — linked to the CLU gene — had unique characteristics in white matter (the bundles of nerve cells) in multiple brain regions, including in some areas known to become damaged in Alzheimer’s disease. The findings suggest that changes in myelin, the substance that protects nerve cells, may be a sign of increased risk of developing the disease later in life.
“Alzheimer’s has traditionally been considered a disease marked by neuronal cell loss and widespread gray matter atrophy,” Thompson said in a news release. “But degeneration of myelin in white matter fiber pathways is more and more being considered a key disease component and another possible pathway to the disease, and this discovery supports that.”
People who have this particular mutation in the CLU — which is common — aren’t doomed to develop Alzheimer’s disease, the authors noted. And young people who have these changes in white matter are not cognitively impaired. But knowledge about this genetic risk could be used to help prevent the disease later in life, the authors said.