Sample from a leukopharesis of a patient with acute promyelocytic leukemia (APL) with a t(15;17) and a white blood cell count of 185,000 with 97% myeloblasts at diagnosis treated with 1uM ATRA for 5 days. Target preparation and hybridization as described in Stegmaier et al., Nature Genetics 2004. Keywords = APL Leukemia