Allele frequency differences between the high and low body weight selected lines.

An association test for comparison B in Figure 2 shows a big difference in how quickly allele frequencies change between generation 40 and 50 in the high- and low lines. In the region between 60 and 80 Mb on chromosome 4 there are large differences between the results from generations 40 and 50. The sliding window mean of 20 markers is shown as a red line for generation 40 and as a purple line for generation 50. The scale is normalized for easier comparison between the time points because their maximum χ² is different (80 at generation 40 and 118 at generation 50).