MLL-AF1q fusion resulting from t(1;11) in acute leukemia

The MLL gene, located on chromosome band 11q23 is fused to different partne r genes as a result of various chromosomal translocations in hematopoietic malignancies. A t(1;11) (q21;q23) resulting in a MLL-AF1q fusion gene has p reviously been reported. Cytogenetic studies on six cases are reported, inc luding one three-way translocation. FISH analysis using a YAC encompassing the MLL gene and a YAC encompassing the AF1q locus showed splitting in thre e cases and two patients, respectively. PCR analysis of two cases confirmed that AF1q is specifically associated with t(1;11)(q21;q23). The MLL-AF1q f usion mRNA was similar to that previously described in one case and involve d MLL exon 7 in the other. This study confirms the specific involvement of AF1q in t(1;11) (q21;q23)-positive acute leukemia with monocytic involvemen t.