title: Hematologic manifestations associated with deletions of the long arm of chromosome 20.
abstract: We investigated 20 patients with hematologic disorders who had a clone of cells with a deletion of most of a chromosome #20 long arm (20q-) in the bone marrow. Three patients had polycythemia vera (PV), 6 had acute nonlymphocytic leukemia (ANLL), 8 had preleukemia (PL), and 3 had other myeloproliferative disorders. In our laboratory, a 20q- chromosome is found in 6% of patients with PV, 3% of patients with ANLL, and 1% of patients with PL. Among the 6 patients with ANLL and a 20q- abnormality, 3 had erythroleukemia. There were no apparent clinical differences among our patients with 20q- chromosomes compared with other patients with similar disorders who did not have a 20q- chromosome. The breakpoint of the 20q- anomaly, in each instance, was in band 20q11, but it occurred near the centromere at 20q1101 in 16 patients and at the distal part of this band at 20q1109 in 4 patients. Three of the 4 patients with a breakpoint at 20q1109 had PL.
mesh_terms: D000368:Aged; D002871:Chromosome Banding; D002872:Chromosome Deletion; D002903:Chromosomes, Human, 19-20; D005260:Female; D006801:Humans; D007621:Karyotyping; D007938:Leukemia / Q000235:genetics; D008297:Male; D008875:Middle Aged; D009196:Myeloproliferative Disorders / Q000235:genetics*; D011087:Polycythemia Vera / Q000235:genetics; D011289:Preleukemia / Q000235:genetics