Autoradiographs from LOH analysis with microsatellite markers. PCR products were separated by polyacrylamide gel electrophoresis, showing examples of allelic loss found in patient E. DNA samples isolated from leukemic cells in the acute phase are labelled as A and those DNA samples isolated from corresponding normal peripheral leukocytes after complete remission are designated as C. Microsatellite markers are indicated above the autoradiograms. Arrows, loss of one allele.