Evidence for Hitchhiking of Deleterious Mutations within the Human Genome
The ratio of deleterious (DEL) to neutral (NEU) SNPs is higher in hitchhiking relative to non-hitchhiking regions (A). The rate of neutral SNPs is reduced (B) and the rate of deleterious SNPs remains relatively constant (C) in hitchhiking compared to non-hitchhiking regions. The x-axes in panels A–C denotes the minimum number of methods used to define hitchhiking regions. Non-hitchhiking regions are labeled by a dash (–). The ratio of deleterious to neutral SNPs is higher in hitchhiking to non-hitchhiking regions for the majority of tests of selection (D). Tajima's D was used by two studies: 1 and 2. Bars show 90% confidence intervals, one, two and three stars indicate P<0.05, P<0.01, and P<0.001 based on a one-sided Fisher's Exact Test.