New research suggests that an evolutionary adaptation in the brain may contribute to the development of Alzheimer’s disease and other related diseases. The theory stems from George Williams theory proposed in 1957, which states adaptations that made human more fit in their early years may make them more vulnerable to disease in post-reproductive years. Han Liang from the University of Texas MD Anderson Cancer Center has been doing research to test this theory, specifically how it relates to Alzheimer’s disease. The researchers examined enhancers in the body. Enhancers are sections of DNA that boost the activity of specific genes altering specific protein levels. Enhancers have previously been identified as an integral drive of human evolution. Liang’s team found that genes under the control of the fastest evolving enhancers were important in human brain development. They also found evidence to suggest that these enhancers and genes are involved in the development of Alzheimer’s disease, Parkinson’s disease, type 2 diabetes, hypertension and osteoporosis. As they looked deeper they found that some of the genes regulated by enhancers were suppressed by a gene called REST, which opposes the progression of Alzheimer’s disease. With functional enhancers, the gene activity is increased and the REST gene is unable to properly function, reducing the protective function of REST. Thus as important as these enhancers may be for brain development in our early years, they could have major consequences as we age. Liang’s research is very unique and more studies should be done before we make conclusions, but this evidence could open a new avenue of research.
SOURCE: The Scientist: https://www.the-scientist.com/?articles.view/articleNo/54716/title/Aging-Related-Diseases-May-Be-a-Negative-Outcome-of-Human-Evolution/
AUTHOR: Sukanya Charuchandra
DATE RETRIEVED: May 31, 2018