CLONALITY ANALYSIS OF CHILDHOOD ALL IN REMISSION - NO EVIDENCE OF CLONAL HEMATOPOIESIS

We studied 98 female patients in remission (2-240 months) from childho od ALL to determine the clonality status of their hematopoiesis. Thirt y-one (31.6%) were heterozygous at the PGK locus for the BstX1 endonuc lease restriction site, permitting X-linked clonality assays to be per formed. Two patients were in relapse at the time of study and were exc luded. We used the PGK-PCR clonality assay (PPCA) to analyze DNA from PMN and mononuclear cells of the remaining 29 female patients. All (29 /29) patients demonstrated polyclonal hematopoiesis. These data show t hat remission from childhood ALL involves reestablishment of polyclona lly derived hematopoiesis in all patients studied.