Small but consistent spatial base percentage gradient in Illumina sequencing. Figures 3A, 3B and 3C show the average percentage of the A base, average percentage of the C base and the genome hit count in each tile within an Illumina lane for the same sample. The x-axis labels and the y-axis labels on the left side are the column and row numbers of tiles. The y-axis labels on the right side of the heatmap scale are the values associated with heatmap colors.
Dai et al. BMC Genomics 2010 11(Suppl 4):S7 doi:10.1186/1471-2164-11-S4-S7