Detection of gfp in the genomic DNA of the peripheral WBCs from a Bcr-Abl–BMT mouse with the myeloproliferative disorder. Genomic DNA isolated from the unsorted WBCs (lane 1) and sorted GFP-negative (lane 2) and GFP-positive (lane 3) cells was subjected to PCR analysis using a mixture of primers that amplify the gfpgene (850 bp) and intron-3 of the mouse c-abl gene (500 bp). The amplified c-abl product was used as an internal positive control for the genomic DNA PCR.