Chiharu Shigeta

Loss of heterozygosity at D3S2 locus of short arm of chromosome 3 in chronic myelogenous leukemia

Loss of heterozygosity (LOH) on the short arm of chromosome 3 was studied in four patients with chronic myelogenous leukemia (CML). The bcr gene rearrangement-negative spleen cells and a B-cell line were used as normal tissue controls. Five probes showing restriction fragment length polymorphisms (RFLP) and a variable number of tandem repeats on chromosome 3 were used. DNA patterns in Southern blotting were compared between normal cells and leukemic cells. One of the four patients had LOH at the D3S2 locus mapped to 3p14.3-3p21.3. The LOH was detected in the blastic phase, but not in the chronic phase. This patient showed normal chromosomes 3 in the blastic phase. These data suggest the possibility of the existence of LOH in CML, occurring as a secondary event in the blastic phase, and which might have been induced by submicroscopic deletion or somatic recombination.

Chronic myelogenous leukemia and Klinefelter's syndrome.

A case of chronic myelogenous leukemia with Klinefelters syndrome mosaicism in a 27‐yr‐old male is reported. Cytogenetic analysis provided evidence that the Philadelphia chromosome occurred monoclonally in the XXY cells but not in the XY cells.

XYY male and hematologic malignancy

Two cases of XYY male with refractory anemia with excess of blasts are reported, and previous reported XYY males with hematologic malignancy are reviewed. Altogether 26 cases were collected for analysis: acute myeloid leukemia (10), acute lymphocytic leukemia (seven), acute leukemia (two), chronic myelocytic leukemia (three), myelodysplastic syndrome (three), and essential thrombocythemia (one). The age at the time of diagnosis ranged in age from 7.5 to 81 years. In three of six XYY/XY mosaicism cases, XYY clone was associated with malignancy. However, in two cases XYY clone was not involved. The evidence presented here suggests that the event of an XYY male with hematologic malignancy is incidental rather than a genetic etiology.