Ancient DNA can both diminish and defend modern minds
CEM Faculty member Benjamin Trumble uncovers genetic mysteries in the modern world. His research with the Tsimane suggests that the globally present ApoE4 allele helps maintain cognitive abilities in environments where humans might be at risk of parasites and infections. The same allele can actually further decline cognitive abilities in our modern post-industrial lifestyles. The article Apolipoprotein E4 is associated with improved cognitive function in Amazonian forager-horticulturalists with a high parasite burden was published in the FASEB Journal on December 28, 2016.
Trumble's research was also part of a feature article written by Ed Yong for The Atlantic. In his interview Trumble notes, “It doesn’t make sense...You’d have thought that natural selection would have weeded out ApoE4 a long time ago. The fact that we have it at all is a little bizarre.” But this is due to the fact that the same gene in the Tsimane protects them from parasites that cause diseases including memory problems. In our post-industrial world, relatively new on our evolutionary time scale, our genes are now responding to a lack of parasites. This response in people who still have this gene is often, unfortunately, Alzheimer's.