Cytogenetic findings in pernicious anaemia. Comparison between results obtained with chromosome studies and the micronucleus test

To elucidate whether the micronucleus test may be a sensitive test for the demonstration of the occurrence of spontaneous structural chromosomal aberrations in human disease, bone-marrow smears and chromosome preparations were studied from ten patients with pernicious anaemia. An increased incidence of metaphases with structural chromosomal aberrations was seen in three of the patients, whereas an increased number of bone-marrow cells containing micro-nuclei was present in eight of the ten patients. The micronucleus test may thus be a rapid and sensitive test to demonstrate whether spontaneous structural aberrations of the chromosomes are present in a group of patients suffering from various diseases.

Chromosome studies of bone marrow cells and peripheral blood lymphocytes from diphenylhydantoin-treated patients

Chromosome studies were performed on both bone-marrow cells and peripheral blood lymphocytes from ten patients with epilepsy, treated with diphenylhydantoin alone. There was no evidence of chromosome damage. Furthermore, the bone-marrow smears from five of the patients were studied for the presence of micronuclei. There was no increase in the number of micronuclei compared with control persons. Conflicting results about the cytogenetic effect of diphenylhydantoin have appeared in the literature. It is emphasized that, in studies on the chromosome-damaging effect of chemical agents in man, bone marrow cells seem to be most indicative of the conditions in vivo.

Marker chromosome 14q+ in non-endemic Burkitt's lymphoma

The chromosomal aberrations in tumor cells obtained by bone marrow aspiration from a patient with non-endemic Burkitt's lymphoma (BL) are reported. Twenty percent of the cells contained the marker chromosome 14q+ earlier described in endemic Burkitt's tumors. Other marker chromosomes were dound only in mitoses which did not contain the 14q+.

Trisomy 8 in acute myeloid leukaemia: A non-random event. Lack of correlation with prognosis and cytokinetic parameters

6 cases of AML with a supernumerary chromosome 8 as the only aberration in practically all bone marrow mitoses and 10 cases with a normal chromosome composition of the marrow cells were investigated in order to evaluate the possible influence of trisomy 8 on some clinical and cytokinetic parameters. No significant differences between the groups were found. In our laboratory a supernumerary chromosome 8 is present in 36% of AML cases with chromosomal aberrations.

Cytogenetic studies in sideroblastic anemia

Cytogenetic studies were performed on bone marrow aspirates from seven patients with acquired sideroblastic anemia. In one male patient a 45,X cell line was present in each of three bone marrow aspirates. The remaining six patients had a normal chromosome complement. The abnormal stem line in the bone marrow may be unrelated to the hematologic disorder or may indicate a neoplastic process still latent. The cytogenetic literature on sideroblastic anemia is reviewed.

Studies on the haematologic and cytogenetic effect of lithium

The corpuscular elements of the peripheral blod and the morphology and chromosome constitution of bone marrow cells have been studied in patients before and during lithium therapy as well as in patients who had received lithium for a substantial period. Lithium therapy produced elevated total white cell, granulocyte, eosinophil and thrombocyte counts and a lymphocytopenia, whereas no effect was seen on the erythrocyte and reticulocyte counts. There were no morphological or cytogenetic changes in the bone marrow aspirates. Neither were toxic doses of lithium able to produce chromosome abnormalities in rats.

Cytogenetic studies in myelomatosis

Cytogenetic studies have been carried out on bone marrow aspirates from 25 patients with myelomatosis. Abnormal stem lines were present in 7 of the patients; the remainder had a diploid chromosome complement. In most patients - also in those without an abnormal clone - some metaphases had a blurred appearance similar to that seen in bone marrow aspirates from patients with acute leukaemia. In many of the chromosome preparations obtained before cytostatic therapy some metaphases with structural aberrations on the chromosomes were seen. Evidence is presented that in the patients with abnormal stem lines in the bone marrow, the chromosome abnormalities are confined to the myeloma cells and are not found in the erythrocytic or granulocytic precursors, which thus do not seem to be involved by the neoplastic process. Based on the present resuts and on a review of the relevant literature some general cytogenetic features are emphasized which may contribute to a better understainding of the disorder. Especially, it is demonstrated that in myelomatosis the cytogenetic changes are much more uniform than in other malignant disorders with the exception of chronic myeloid leukaemia.