Inspection of the second axis of the Northern European subset (see Figure 4A and 4B), also showed an unexpected grouping of individuals on the Y axis into three separate groups. When we ascertained informative SNPs between the top and bottom groups, all of the SNPs with In values >0.02 were found to be located in a 3.8 Mb segment of human Chromosome 8 (8.135 – 11.936 Mb). This region has been previously shown to contain a common inversion within European populations [24,25]. When only SNPs within this interval were used the distribution of the individuals formed the same grouping of three clusters as found using the entire 500K set (data not shown). As expected two dominant haplotypes (A and B) were ascertained with twenty selected markers with very large Ins and described the same three individual groups (AA, AB, and BB) and were highly correlated (r2 = 0.83) (Figure 5). Although the λgc in the entire NARAC case-control dataset is decreased from 1.073 to 1.048 by considering this axis, our analyses indicate that the position of individuals on this axis
