Leukemic cells from TEL-JAK2 transgenic mice express CD8 lineage-associated genes. Quantitative RT-PCR analysis of Ctsw, Prf1, and Runx3 mRNA levels normalized for Hprt expression performed for 4 independent wild-type thymocyte samples, wild-type CD8 SP splenocytes, and thymic leukemic cells from the indicated transgenic TEL-JAK2, TEL-JAK2/Ptcra^−/− and TEL-JAK2/Rag2^−/− mice. Means and standard deviations were calculated as described in “Materials and methods.”