Figure 9. Biological Validation: overlap with cardiac H3K27ac sites.

OccuPeak, MACS and CisGenome were used to call peaks from the TBX3 and the two replicate p300 ChIP-seq datasets. Peaks were then sorted on peak significance and overlap with cardiac enhancers was determined. For visualization, the number of most significant peaks was incremented in steps of 1000 peaks. Overlap of peaks with H3K27ac sites was assessed as measure for active enhancers. In the p300(2) dataset the performance of OccuPeak was significantly better when only uniquely mappable tags were considered. The results of the statistical comparison at the maximum common number of peaks (vertical dotted line) is given as a string in which ' = ' indicates that the overlap is not significantly different between the methods and '>' that the overlap differs significantly at p<0.0001 or less (O = OccuPeak, all reads; OU = OccuPeak, uniquely mappable reads; M = MACS; C = Cisgenome).