COMPLETE EXON STRUCTURE OF THE ALL1 GENE

The ALL1 gene is found rearranged in approximately 10% of acute lympho blastic leukemias and in over 5% of acute myeloid leukemias, The gene undergoes fusion with either a variety of partner genes located on dif ferent chromosomes or with itself, To further characterize the role of the ALL1 gene in the leukemogenic process, and possibly in solid mali gnancies, we defined its complete genomic structure, The gene, which s pans a region on chromosome band 11q23 approximately 90 kb in length, consists of 36 exons, ranging in size from 65 bp to 4249 bp, The deter mination of intronic sequences flanking the exon boundaries will allow the determination of whether point mutations may be responsible for i nactivation of the gene in solid tumors showing loss of heterozygosity at region 11q23.