E2A^−/− DN2 thymocytes have altered expression of T lymphocyte– and NK cell–associated genes. (A) qPCR analysis of Notch1 and Deltex1 mRNA in E2A^+/+ and E2A^−/− ETPs and DN2 and DN3 thymocytes. Expression was normalized to Hprt and shown relative to E2A^+/+ ETPs. Data are combined from 3 experiments with triplicate measurements. (B) Pie graph shows the percentage of genes that were differentially expressed between E2A^+/+ and E2A^−/− DN2 cells as determined by microarray analysis. (C) Heat maps show differential gene expression in E2A^+/+ and E2A^−/− DN2 cells. (D) Relative change in expression for a selected set of genes that decreased or (E) increased in E2A^−/− compared with E2A^+/+ DN2 cells. Error bars represent the SE from triplicate microarray experiments.