Karyotypic and clinical findings in a consecutive series of children with acute lymphocytic leukemia

Detailed karyotypic findings and clinical data on 70 consecutive newly diagnosed children with acute lymphocytic leukemia (ALL), primarily from Indiana, are presented. These children fall into five karyotypic groups: (a) normal chromosomes; (b) hyperdiploid I, with chromosome numbers greater than 50, frequently with multiple copies of the same chromosome, and often lacking a consistent abnormal clone; (c) hyperdiploid II, with karyotypes having 47-49 chromosomes and usually with all of the karyotypically abnormal cells identical; (d) pseudodiploids, with either translocations or deletions of specific chromosomes; and (e) hypodiploids. Because few of this series of children have expired or relapsed, patients in the karyotypic groups have been considered in relation to those clinical factors that have been found to be of prognostic significance by the Children's Cancer Study Group. Age, white blood cell count, and platelet count were significantly different in patients among the five karyotypic groups. A significantly greater number of pseudodiploid patients had white blood cell counts greater than 50,000 X 10(6)/L and were not in the infant age group, as has been the case for other series. Specifically, the 4;11 translocation was associated with a higher risk of early death compared with other patients. Among those with normal karyotypes, platelet levels of greater than 100 X 10(9)/L occurred more frequently than among those with abnormal karyotypes.

Localization of the human salivary protein complex (SPC) to chromosome band 12p13.2

In situ hybridization of a 3H-labeled probe containing a fragment from PRP-1, a genomic clone with human salivary proline-rich protein gene sequences, revealed significant labeling on the short arm of human chromosome 12 in metaphase preparations from two individuals. Fifty-three percent of metaphases exhibited labeling on one or both chromosomes 12. Additional cells scored at the 850-1,000 band level revealed a significant proportion (52% [32/61] grains, p less than 0.005) of the labeled sites on chromosome 12 to be on band 12p13.2. This probe for a human salivary proline-rich protein gene fragment, probably PMS, is from a cluster of 13 linked genes designated as the human salivary protein complex (SPC). Studies of the DNA of human-mouse somatic-cell hybrids have assigned the SPC to chromosome 12, but have not provided a regional localization (Azen et al, 1985). This paper reports the localization of the SPC to a specific chromosomal band, 12p13.2.

Comparison of directly prepared and cultured cells in karyotypic analysis of all

An evaluation of methods for studying bone marrow obtained from patients with acute lymphoblastic leukemia indicates that both directly prepared and cultured cells are necessary for complete karyotypic analysis, but that both synchronized and unsynchronized cultures may not be necessary.

Terminal and interstitial deletions of the long arm of chromosome 7: a review with five new cases

Sixteen cases of terminal deletions and 17 cases of interstitial deletions of the long arm of chromosome 7 have been reported to date. We present two new cases of the former and three of the latter. The somatic changes in these patients are tabulated and an update on the anomalies associated with the various cytogenetic entities is presented. Changes found in over one-third of patients with 7q terminal deletion syndrome include: developmental delay, pre- and postnatal growth retardation, generalized hypotonia, abnormal electroencephalograms with or without seizures, feeding problems in infancy, microcephaly, prominent forehead, ocular hypertelorism, eye defects, broad nasal bridge, bulbous nasal tip, auricular malformations, micrognathia, chest abnormalities, genital malformations in males, and abnormal palmar and plantar creases. Evidence for the localization of the Kidd blood group gene on chromosome 7 distal to band q32, as suggested by previous reports, is reviewed; we conclude that the evidence does not warrant placement of the gene in this region of the genome.

Elevated sister chromatid exchange and cell cycle analysis in bone marrow in childhood ALL

Sister chromatid exchange (SCE) frequencies were analyzed in both stimulated and unstimulated bone marrow samples from eight patients recently found to have childhood acute lymphocytic leukemia (ALL). Six of the patients had elevated SCE frequencies in stimulated marrow when compared to control values. In unstimulated marrow, all four patients had elevated SCE frequencies. These data agree with peripheral leukocyte findings in ALL. Cell cycle analysis revealed no significant differences between the patient marrows and the control marrows. Since no correlation between cell cycle distribution and SCE frequency was found, it is suggested that the differences in SCE observed may be related to the type of proliferating cell.

The myeloproliferative reaction in a child with Down syndrome: cytological and chromosomal evidence for a transient leukemia

Infants with Down syndrome occasionally develop marked myeloproliferative reactions (MPR) indistinguishable from acute myelocytic leukemia but which spontaneously regress. Most authors have attributed MPR to immature or defective control on bone marrow development. In this report serial cytomorphologic and chromosomal findings in the bone marrow and peripheral blood of a child with the MPR suggests that MPR may be due to a spontaneously regressing clone of malignant cells. At the height of the myeloproliferative response, chromosomal studies demonstrated a clone of blast-like cells with a 21-22 translocation consistent with Down Syndrome and an X-8 translocation which was present only in the initial peripheral blood analysis harvested at 24 hours but was not present in the 72 hours samples. This X-8 translocation was not demonstrated in bone marrow or peripheral blood samples obtained at random times throughout the one year followup. During this period there was complete resolution of the MPR. In addition the chromosomes from one cell demonstrated several double minutes at the time of the MPR. Double minutes have previously been reported only in malignant diseases, especially tumors of neural origin and leukemia. These findings raise questions about the benign origin of the MPR and support the idea the MPR may be the result of a spontaneously regressing clone of malignant cells.