title: ETV6-RUNX1 Rearrangement in Tunisian Pediatric B-Lineage Acute Lymphoblastic Leukemia.
abstract: In this study, Forty-one out of fifty-seven Tunisian children with B-lineage acute lymphoblastic leukemia (B-ALL), and without cytogenetically detectable recurrent abnormalities at the time of the diagnosis, were evaluated by fluorescence in situ hybridization (FISH) for the t(12;21). This translocation leads ETV6-RUNX1 (previously TEL-AML1) fusion gene. 16 patients (28%) had ETV6-RUNX1 rearrangement. In addition to this rearrangement, two cases showed a loss of the normal ETV6 allele, and three others showed an extra signal of the RUNX1 gene. Seven patients without ETV6-RUNX1 rearrangement showed extra signals of the RUNX1 gene. One out of the 7 patients was also associated with a t(3;12) identified by FISH. This is the first Tunisian study in which we report the incidence of t(12;21) among childhood B-lineage ALL and in which we have found multiple copies of RUNX1. Finally, our findings confirm that additional or secondary genetic changes are commonly encountered in pediatric B-lineage ALL with ETV6-RUNX1 gene fusion which is envisaged to play a pivotal role in disease progression.
authors.affiliation: Laboratoire de Cytogénétique et de Biologie de la Reproduction, CHU Farhat Hached, Sousse 4000, Tunisia.
authors.forename: Abir
authors.initials: A
authors.lastname: Gmidène
authors.forename: Hatem
authors.initials: H
authors.lastname: Elghezal
authors.forename: Hlima
authors.initials: H
authors.lastname: Sennana
authors.forename: Yosra
authors.initials: Y
authors.lastname: Ben Youssef
authors.forename: Balkiss
authors.initials: B
authors.lastname: Meddeb
authors.forename: Moez
authors.initials: M
authors.lastname: Elloumi
authors.forename: Abderrahim
authors.initials: A
authors.lastname: Khlif
authors.forename: Ali
authors.initials: A
authors.lastname: Saad