Assessing the impact of Neanderthal admixture on seven human phenotypes

Abstract

In recent years, the Neanderthals have been the subject of many studies. In 2010, the availability of a sequenced genome from this species heralded a revolution in the world of ancient genomics. It is now known that there was admixture between the Neanderthals and modern humans tens of thousands of years ago. As a result, all present-day non-Africans can trace 1.5-2.1% of their genomes to Neanderthals. Following these discoveries, many studies have attempted to test for association between fragments of Neanderthal ancestry and various phenotypes in contemporary humans. Here, we present results from of differential phenotypic impact of Neanderthal and non-Neanderthal alleles based on genome-wide association studies (GWAS). We applied our analyses to seven phenotypes. Our results suggest that the Neanderthal alleles tend to increase the height of contemporary people. We also detect increasing effects on triglyceride levels and white blood cell count.Furthermore, we found evidence for directional selection having influenced some phenotypes of humans during past millennia – towards greater height, lower BMI, higher levels of high-density lipoprotein (HDL) and greater capacity for educational attainment.