Journal of Neurology: Amyloid Plaque Accumulation in the Brain Tied to the Environment
Image: Jensflorian / Wikimedia Commons
Scientists at the University of South Wales have discovered for the first time how genes and the environment contribute to the development of Alzheimer's disease. To do this, the researchers studied identical and dizygotic twins by measuring the accumulation of amyloid plaques in the brains of patients using positron emission tomography (PET). This is reported in an article published in the Journal of Neurology.
Scientists often use the study of identical twins, whose genomes are almost 100 percent identical, in order to link the effects of genes and environmental factors with the development of various diseases. Any phenotypic or behavioral differences in identical twins are likely to be due to powerful environmental factors, despite many similarities. Dizygotic or fraternal twins, who also grow up together, have only 50 percent identical genes, that is, their genetic differences, on the contrary, are stronger than the differences in environmental factors.
The study involved 61 pairs of identical twins and 42 dizygotic couples at the age of 71, who underwent PET scans to detect the accumulation of amyloid, a protein that begins to accumulate in the brain in the early stages of Alzheimer's disease. It turned out that genes play only a moderate role in the accumulation of amyloids in the brain.
However, experts have not yet been able to figure out which third-party factors contribute to Alzheimer's disease. Thus, hypertension, diabetes, high cholesterol or heart disease were not associated with the risk of amyloid accumulation in the brain. The authors of the work note that more extensive research is needed.
