Chromosome Studies in Human Leukemia. I. Acute Leukemia in Children23

Abstract

Metaphase chromosome number and morphology were investigated in short-term cultures of leukocytes from the peripheral blood of 7 children with acute leukemia, ranging in age from 3 months to 11 years, and of 2 nonleukemic children, both 6 years old. Leukocytes from the 2 nonleukemic children showed no significant departure from the diploid chromosome number (2n = 46). In 10 karyotype analyses on each of the 2, no detectable structural changes were present in the chromosomes. In all the leukemia cases, the majority of cells also had 46 chromosomes. From 5 to 15 karyotype analyses were made in each case, and the majority of these cells had numerically and morphologically normal chromosome complements. Such structural changes as were present revealed no characteristic pattern. In the 3 cases which had undergone extensive therapy, and in which symptomatic disease had been present for from 6 months to 3 years, the incidence of karyotype change was higher than in the remaining 4 cases, 3 of which were untreated and the fourth of which had been treated for only 5 days. These data are interpreted to indicate that the observed chromosome changes are not causally related to the onset of the disease.