A new study by University of Pennsylvania researchers investigating recent signals of positive selection of genes across human populations reveals the concurrent emergence of alcohol dehydrogenase (ADH) gene variant in various populations across the globe without direct genetic heritage. The study has been published in the journal Nature, Ecology & Evolution utilized the 1000 Genome Project data and analyzed 2500 individuals from 20 populations across four continents.
ADH is a group of enzymes normally present in humans to break down the alcohol. But the emergent gene variant of the ADH increases enzyme activity resulting into the less effective breaking down of the alcohol consequently, leading to adverse physical response to alcohol consumption.
People with this specific genetic variant may feel sick after drinking alcohol and henceforth, are unlikely to develop a taste for alcohol or become alcoholic.