H. Kempski et al., An investigation of the t(12;21) rearrangement in children with B-precursor acute lymphoblastic leukaemia using cytogenetic and molecular methods, BR J HAEM, 105(3), 1999, pp. 684-689
The t(12;21) is the commonest recurrent translocation in childhood acute ly
mphoblastic leukaemia (ALL), the presence of which has been suggested to be
a good prognostic feature. We have studied 22 childhood cases of B-precurs
or ALL with this rearrangement, and have found no significant differences i
n event-free survival between these and a control group of patients with si
milar phenotypes. Using a variety of cytogenetic and molecular techniques,
we have confirmed a strong association with co-expression of myeloid marker
s, frequent deletions of the short-arm of the untranslocated chromosome 12
homologue and duplication of the derivative chromosome 21, Intragenic delet
ion of the untranslocated ETV6 gene in 3/12 informative patients points to
the likelihood of this gene being a target for deletion.