First, the RPC genes identified using the Fisher’s exact test that were used for classifying the single cells were examined. Second, hierarchical clustering was performed on the set of single cells including the 42 RPCs and the 21 developing neurons previously characterized using Gene Cluster software. Finally, genes with potentially interesting RPC expression patterns were identified by visual inspection of the microarray data in Microsoft Excel. The types of genes identified ranged from transcription factors to secreted molecules. The presence of these transcripts in many of the RPCs continued to demonstrate the robustness of the single cell profiling method since these genes have been shown to be Angoroside-C expressed in the retina by other means. Classical birthdating experiments have shown that the different retinal cell fates are produced at different times during the course of retinal development. In addition, heterochronic mixing experiments demonstrated that RPCs could only produce the temporally appropriate cell fates when placed in an environment of a different developmental stage. Given these results, it was expected that a comparison of the single cell profiles from E12.5 RPCs to those of P0 RPCs would reveal genes that were expressed primarily in either early or late RPCs. Secreted frizzled-related protein 2,Atractylenolide-I a gene previously identified in a retina SAGE screen, was in fact only observed in early RPCs and its expression was almost completely extinguished by P0. Examining gene clusters generated around Sfrp2 either by hierarchical clustering methods or by using a Fisher’s exact test did reveal some genes with correlated expressions in RPCs, but consistently failed to yield genes with a close match for the temporal expression pattern of Sfrp2. Most of the associated genes were expressed in RPCs at timepoints beyond when Sfrp2 was detected. Comparing the gene expression profiles of E12.5 RPCs and P0 RPCs by visual inspection in Microsoft Excel, however, did reveal several candidate genes whose expression appeared mainly confined to early RPCs. There were not a large number of these genes and their expression was restricted to a small subset of the profiled RPCs, unlike Sfrp2, which was more broadly expressed in early RPCs.