A case of acute myeloblastic leukemia with chromosomes showing 46, XY = 11/46, XY, 21q- = 39.

Chromosome studies were performed on a 55-year-old male with the clinical diagnosis of acute myeloblastic leukemia. Cytogenetic studies of the bone marrow cells using the quinacrine fluorescence banding and trypsin-Giemsa banding techniques revealed the karyotype 46, XY = 11/46, XY, 21q- = 39. No. 21 chromosome abnormalities in patients with acute myeloblastic leukemia have been amply demonstrated. However, no case of deletion of long arm of chromosome No. 21 has ever been reported in the literature, and it seems that our case is the first report. In view of the rarity of this case, a brief report seems warranted.