[Relationship between the occurrences of AL, MDS and AA and abnormal BM proliferation of patient's parents].

After studying of familial leukemias, Myelodysplastic Syndrome (MDS) and aplastic anemia (AA), we observed and analysed bone marrow (BM) cells hematologically and molecular-cytogenetically in 36 persons who are first degree relatives (FDRs) of patients with acute leukemias (AL), MDS and AA. The peripheral blood (PB) lymphocyte chromosome fragility sensitive to folic acid and unstability was also analysed in 18 FDRs. The abnormal BM megakaryocystic/erythroid cellularity and the rearrangement of c-erbB were found in 66%-86.1% of parents and siblings of patients. The associations of dysplastic megakaryopoiesis, including the presence of lymphoid small megakaryocytes, with the chromosomal monosomy or/and the rearrangement/amplification of C-erbB, were found in a few parents and siblings. These results were consistent with those of MDS, Fanconi Anemia (FA) and AL. The normal karyotype and SCD positive of BM cells and PB lymphocytes, and PB lymphocyte chromosomal fragility and unstability were found in most of patients' parents, while familial chromosomal monosomy of BM cells and PB lymphocyte chromosomal fragility were found in parents and siblings of familial leukemia patients. Based on the studies of a large family with 7 cases of acute erythroleukamia and relative myeloleukemias in three consecutive generations and a family with 3 CAA and 1 AML, the rearrangement of c-erbB might be inherited. The rearrangement/amplification of c-erbB and its PCR detected results could be the indicators of gene diagnosis of preleukemia and might be useful in genetic conselling of leukemias. The common origin of AL, MDS and AA was discussed.