title: Tetraploid karyotype (92,XXYY) in two patients with acute lymphoblastic leukemia.
abstract: Tetraploid karyotypes without structural chromosome abnormalities were found in approximately 50% of the bone marrow cells in two patients with acute lymphoblastic leukemia with L2 morphology and "null cell" immunophenotype. Strict tetraploidy (4n = 92) has not been reported as the sole karyotypic rearrangement in bone marrow neoplasia, but may represent a previously unrecognized cytogenetic leukemia subtype.
mesh_terms: D002675:Child, Preschool; D002871:Chromosome Banding; D006801:Humans; D007621:Karyotyping; D007945:Leukemia, Lymphoid / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011123:Polyploidy