Clonal analysis of chemoprotected hematopoiesis in dogs G179 and G197. LAM-PCR analysis of DNA derived from peripheral blood and bone marrow from (A) dog G179 and (B) dog G197. (A) Pre indicates before the first cycle of drug administration; early, after the first 4 cycles of drug administration; and late, after the last cycle of drug administration. (B) Pre indicates before the first cycle of drug administration; early, after the first 5 cycles of drug administration; late-1, immediately after the last cycle of drug administration; and late-2, approximately one month after the last cycle of drug administration. The far left lane in both panels is a 25–base pair (bp) size marker. The number of clones decreases with increasing number of drug cycles. Importantly, polyclonality is preserved throughout the course of the study in both dogs.