Cytogenetic evidence for a clonal disorder involving CFU-GEMM, BFU-E and CFU-C in patients with myeloproliferative disorders.

We grew multilineage hemopoietic colonies in vitro from 4 patients with myeloproliferative disorders (MPD) having chromosomal aberration, and performed cytogenetic analysis of single CFU-GEMM, BFU-E and CFU-C-derived colonies on Day 14 of culture. In Patient 1 with acute myelofibrosis, CFU-GEMM and BFU-E colonies had only a 47, XX, +C karyotype. In Patient 2 with polycythemia vera, CFU-GEMM, BFU-E and CFU-C colonies all showed the same abnormal karyotype of 46, XY, -12, +der(12)t(1;12). Patients 3 and 4 had primary myelofibrosis, and their respective karyotypes were 46, XY, 13q- and 46, XX, -6, +der(6)t(1;6) in CFU-GEMM, BFU-E and CFU-C colonies. In these 4 patients, the karyotype of bone marrow or circulating mononuclear cells was identical to that of hemopoietic colonies. These results indicate a clonal origin of MPD at the level of CFU-GEMM.