Natural selection has shaped modern human genomes far more than previously thought, a study from Harvard University has shown, looking at ancient DNA from nearly 16,000 people across more than 10,000 years in West Eurasia \u2013 Europe, the Middle East, the Caucasus, and parts of Central Asia and North Africa.<\/p>\n
New technology detected directional selection in ancient DNA time-series data and a consistent trend in how frequent gene variants became over time in 15,836 West Eurasians. As part of this evolution, genes for red hair, coeliac disease and a lighter skin tone were all becoming more common, according to the research.<\/p>\n
Researchers caveated that the growing number of redheads didn\u2019t automatically mean the trait was important in the past.<\/p>\n
\u201cPerhaps having red hair was beneficial 4,000 years ago, or perhaps it came along for the ride with a more important trait,\u201d the study, published in the scientific journal Nature, suggested.<\/p>\n
Author of the study, Ali Akbari, senior staff scientist in the lab of Harvard geneticist David Reich, said these new technologies would allow a greater understanding of natural selection.<\/p>\n
\u201cWith these new techniques and a large amount of ancient genomic data, we can now watch how selection shaped biology in real time,\u201d he said. \u201cInstead of searching for the scars natural selection leaves in present-day genomes using simple models and assumptions, we can let the data speak for itself.\u201d<\/p>\n
More than 250 archaeologists and anthropologists collaborated with the lab to report new DNA data from 10,016 ancient individuals from West Eurasia, which the geneticists added to another 5,820 published ancient sequences and 6,438 modern ones.<\/p>\n
\u201cThis single paper doubles the size of the ancient human DNA literature,\u201d Mr Reich said. \u201cIt reflects a focused effort to fill in holes that limited the power of previous studies to detect selection.\u201d<\/p>\n
While the study flagged an increased risk of coeliac disease and Crohn\u2019s disease, some human traits suggested an increase in immunity and a lower risk of certain diseases. Immunity to HIV infection and resistance to leprosy were flagged, as well as a lower risk of rheumatoid arthritis, alcoholism, bipolar disorder and schizophrenia. Researchers even marked a lower susceptibility to tobacco smoking.<\/p>\n
It also appeared that a lower body fat percentage, waist-to-hip ratio and body mass index were the result of DNA changes.<\/p>\n","protected":false},"excerpt":{"rendered":"Natural selection has shaped modern human genomes far more than previously thought, a study from Harvard University has…\n","protected":false},"author":2,"featured_media":402973,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[61,60,898,82],"class_list":{"0":"post-402972","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-science","8":"tag-ie","9":"tag-ireland","10":"tag-latest-news-ticker","11":"tag-science"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/402972","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/comments?post=402972"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/402972\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media\/402973"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media?parent=402972"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/categories?post=402972"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/tags?post=402972"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}