Agriculture, dietary changes, and adaptations in fat metabolism from ancient to modern Europeans
Now, evolutionary biologists are weighing in based on the increasing power of DNA analyses to explore how changes in diet over eons have caused human adaptations to genes regulating fat metabolism . Nestled on the long arm of chromosome 11, two essential genes serve as key traffic police in the synthesis of vital fatty acids. These genes, called fatty acid desaturase 1 and 2 (FADS1 and 2), change dietary fat into components necessary for the heart, brain and muscle. They assist in the conversion of short-chain omega-3 and omega-6 poly-unsaturated fatty acids (PUFAs) to long-chain PUFAs. Scientists have recently shown that FADS genes are frequent targets of natural selection in humans. Before modern humans moved out of Africa, roughly 85,000 years ago, natural selection targeted variants in these genes presumably associated with changes in diet. After people moved out of Africa and encountered new environments, selection again targeted the FADS genes for humans to better adapt t...