title: Tandem triplication and quadruplication of chromosome 21 in childhood acute lymphoblastic leukemia.
abstract: A 5-year-old girl with ALL was shown to have a leukemic clone characterized by a triplication and quadruplication of chromosome 21, arranged in tandem, at diagnosis and relapse, respectively. To our knowledge, this is the second report of this chromosomal anomaly in ALL, which was confirmed by in situ staining. The karyotype evolution in the leukemic clone from triplication to quadruplication at relapse emphasizes the association of chromosome 21 with hematopoietic malignancies.
authors.affiliation: Laboratorio de Citogenética, Hospital de Pediatría Juan P. Garrahan, Buenos Aires, Argentina.
authors.forename: E M
authors.initials: EM
authors.lastname: Baialardo
authors.forename: M S
authors.initials: MS
authors.lastname: Felice
authors.forename: J
authors.initials: J
authors.lastname: Rossi
authors.forename: C
authors.initials: C
authors.lastname: Barreiro
authors.forename: M S
authors.initials: MS
authors.lastname: Gallego
mesh_terms: D000782:Aneuploidy; D002675:Child, Preschool; D002891:Chromosomes, Human, Pair 21 / Q000235:genetics*; D005260:Female; D006801:Humans; D007621:Karyotyping; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics*; D014314:Trisomy / Q000235:genetics