Conventional karyotyping, FISH, SKY and CGH analyses showed that the region distal to the MLL locus on 11q23 was lost and replaced by the distal region of 11p, leading to a partial trisomy of 11p and a partial monosomy of 11q.
Fluorescence in situ hybridization disclosed the presence of an extra copy of the MLL gene on 16p13 and 18p11.2, respectively, as a result of the partial trisomy of chromosome 11q.