title: Double Inv(3)(q21q26), a rare but recurrent chromosomal abnormality in myeloid hemopathies.
abstract: Inv(3)(q21q26)/t(3;3)(q21;q26) is a feature of a distinctive entity of acute myeloid leukemia (AML) associated with normal or elevated platelet count, atypical megakaryocytes and multilineage dysplasia in the bone marrow, as well as minimal to no response to chemotherapy and poor clinical outcome. The presence of an inversion on both chromosome 3s is a rare event, as only eight cases have been reported in the literature. Recently, we identified two patients with AML carrying a double inv(3)(q21q26). Using librairies of bacterial artificial chromosome clones mapping to bands 3q21 and 3q26, we found that the regions in which the breakpoints occurred were different in both patients, but located in the same restricted areas in each patient. Although it cannot be excluded that inversion occurred independently on both chromosome 3s, it is more likely that the presence of a double inv(3) is the result of loss of the normal chromosome 3 followed by a duplication of the inverted chromosome, or segmental loss of heterozygosity followed by a somatic repair mechanism.
authors: Laboratoire de Cytogénétique, Hôpital Morvan, Bâtiment 5bis, CHRU Brest, 2, avenue Foch, F-29609 Brest cedex, France. marc.debraekeleer@univ-brest.fr
authors: Etienne
authors: E
authors: De Braekeleer
authors: Nathalie
authors: N
authors: Douet-Guilbert
authors: Marie-Josee
authors: MJ
authors: Le Bris
authors: Jean-Christophe
authors: JC
authors: Ianotto
authors: Christian
authors: C
authors: Berthou
authors: Nadia
authors: N
authors: Gueganic
authors: Clement
authors: C
authors: Bovo
authors: Audrey
authors: A
authors: Basinko
authors: Frederic
authors: F
authors: Morel
authors: Marc
authors: M
authors: De Braekeleer
mesh_terms: D000368:Aged; D007446:Chromosome Inversion / Q000235:genetics*; D002893:Chromosomes, Human, Pair 3 / Q000235:genetics*; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D015470:Leukemia, Myeloid, Acute / Q000235:genetics*; D008297:Male; D008875:Middle Aged