Candidate regions of positive selection were defined as genomic regions containing an uncharacteristic clustering of SNPs with high iHS statistics. This was quantified as the proportion of SNPs with |iHS| > 2 in the four regions of interest. Candidate regions of positive selection were identified as containing any SNP with an iHS score of |iHS| > 2, as this corresponds to the top ~5% of all scores. The iHS value at a SNP “measures the strength of evidence for selection acting at or near that SNP” however does not provide a formal significance test (Voight et al. 2006).
