Heat map representation over time of the DE miRNAs at 16 wks. The heat map illustrates the fold change differences identified by microarray analysis between xlpra2-mutant and normal retinas at all three ages (3, 7, and 16 wks) for the up-regulated (A) and down-regulated (B) miRNAs at 16 wks. miR-183 and miR-122 were also tested by qRT-PCR, therefore they were also included in spite of their expression differences being not statistically significant. miRNAs are listed from the highest to the lowest fold change difference at 16 wks. The x-axis shows the time points, while the y-axis displays the DE miRNAs at 16 wks. The map contains log2 intensity/fold change ratios that are color coded with red corresponding to up-regulation and blue to down-regulation. Apoptomirs that were selected for qRT-PCR analysis are boxed and marked in bold.