Control (C) and leukemic (L) samples from patient P32, used to create the cell lines 183-Ccl and 183-E95, respectively, and leukemic sample from patient 28 were HindIII digested, fractionated on 1% agarose, and hybridized with the following probes: (A) control probe bcl-1; (B) p9E4.3, with densitometry results compared with control signals of 0.45 and 0.45, respectively, showing hemizygous loss and hemizygous loss, respectively; and (C) probe p6E.32, with densitometry results compared with control signals of 0.02 and 0.79 showing homozygous loss and biallelic retention, respectively.