Fig. 2

Histograms of read coverage of 75 bp fragment reads from the angus steer obtained by summing coverage data from all 31 subcellular libraries of diploid cells and separately for the bulk genomic library. The histogram shows the percentage of the genome at different coverages between one and 29 X. The observed coverage is shown as columns, whilst the expected random Poisson distribution of coverage with mean derived from the data is shown as a line. The observed coverage was truncated at 29 X for clarity, but 17 % of the genome had coverage > 29 X. The coverage of the bulk genomic DNA is only slightly broader than expected from the Poisson distribution, but coverage from fractions of cells is highly skewed