Jumping translocations in multiple myeloma.
Jumping translocations (JT) have been defined as nonreciprocal translocations involving a same donor chromosome arm or chromosome segment onto two or more recipient chromosomes in different cell lines in the same patient, leading to a mosaic karyotype. This definition has been expanded to also include extra copies of a same donor segment on different recipient chromosomes in a single clone. Six patients with multiple myeloma and JT involving chromosome arm 1q were identified among 37 patients presenting with chromosome 1 abnormalities. All six patients had an advanced disease and a short survival. The literature review allowed us to identify 24 additional patients with JT. Chromosomes 16 and 19 were the recipients in 11 (45.8%) and 6 (25%) of these 24 patients, respectively. Breakpoints on the recipient chromosomes were pericentromeric in 46.2% and telomeric in 40.4% of the breakpoints recorded. Since telomeres are made of (TTAGGG)n tandem DNA repeats that are also found in the pericentromeric heterochromatic regions (interstital telomeric sequences), it is presumed that jumping translocations arise through illegimate recombination between telomere repeat sequences and interstitial telomeric sequences.
Jamet
Déborah
D
Laboratoire d'Histologie, Embryologie et Cytogénétique, Faculté de Médecine et des Sciences de la Santé, Université de Bretagne Occidentale, 22 Avenue Camille Desmoulins, Brest cedex F-29285, France.
Marzin
Youna
Y
Douet-Guilbert
Nathalie
N
Morel
Frédéric
F
Le Bris
Marie-Josée
MJ
Herry
Angèle
A
Banzakour
Said
S
Bourquard
Pascal
P
Morice
Patrick
P
Abgrall
Jean François
JF
Berthou
Christian
C
De Braekeleer
Marc
M
D000368:Aged; D002878:Chromosomes, Human, Pair 1; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000235:genetics*; D014178:Translocation, Genetic