Selection trends on nasal-associated SNP variants across human populations

Abstract The human nose has a diversified morphology among different geographical distributions and serves as a natural conditioning system for the inhaled air. Several studies have put forth statistically sound observations of the presence of large-bulbous noses in hot and humid Africa and narrower-aquiline noses in cold and dry Europe. These diverse nasal shapes have been termed as local adaptations to a region's climate. Over the past couple of decades, several GWA studies have linked potential loci with several diseases and morphological traits including the human nasal forms. In this study, highly significant SNPs associated with eight nasal morphological traits from previously reported GWA studies were collected. SNP data was obtained from the 1000 Genomes Project Phase III. By employing tests such as extended haplotype homozygosity (EHH), haplotype bifurcation diagrams and Fst measure, a subset of 6 nasal-associated SNPs were found to be significantly differentiated among the human sub-populations indicating that positive selection has acted on human nasal-associated loci.