Life Sciences Commons^™

Pervasive Hitchhiking At Coding And Regulatory Sites In Humans, James J. Cai, J. Michael Macpherson, Guy Sella, Dmitri A. Petrov

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Much effort and interest have focused on assessing the importance of natural selection, particularly positive natural selection, in shaping the human genome. Although scans for positive selection have identified candidate loci that may be associated with positive selection in humans, such scans do not indicate whether adaptation is frequent in general in humans. Studies based on the reasoning of the MacDonald–Kreitman test, which, in principle, can be used to evaluate the extent of positive selection, suggested that adaptation is detectable in the human genome but that it is less common than in Drosophila or Escherichia coli. Both positive and purifying …

A Kinship-Based Modification Of The Armitage Trend Test To Address Hidden Population Structure And Small Differential Genotyping Errors, Cyril Rakovski, Daniel O. Stram

Mathematics, Physics, and Computer Science Faculty Articles and Research

Background/Aims We propose a modification of the well-known Armitage trend test to address the problems associated with hidden population structure and hidden relatedness in genome-wide case-control association studies.

Methods The new test adopts beneficial traits from three existing testing strategies: the principal components, mixed model, and genomic control while avoiding some of their disadvantageous characteristics, such as the tendency of the principal components method to over-correct in certain situations or the failure of the genomic control approach to reorder the adjusted tests based on their degree of alignment with the underlying hidden structure. The new procedure is based on Gauss-Markov …