title: Unusual location of BCR-ABL1 fusion sequences in a chronic myeloid leukemia patient.
abstract: We describe a case of a chronic myeloid leukemia patient displaying the chimeric BCR-ABL1 gene on 12p11. Chromosome analysis revealed complex chromosome aberration involving chromosomes 9, 12, and 22. Fluorescence in situ hybridization revealed an unusual signal pattern  revealing the BCR-ABL1 fusion signal on chromosome 12, while no reciprocal ABL1-BCR fusion was detected on der(9) chromosome. The relocation of BCR-ABL1 fusion sequences to 12p11 site in our patient represents a rare type of variant translocation, as in almost all patients  the chimeric BCR-ABL1 gene is located on der(22) chromosome. Our case illustrates the challenge of recognizing a complex pattern of cytogenetic aberrations that occur with variant t(9;22) and may add further information about clinical significance of unusual variant Ph rearrangements  in CML patients receiving tyrosine kinase inhibitor treatment.
authors.affiliation: Department of Hematology, Kuwait Cancer Control Center, Shuwaikh, Kuwait. annaadria@yahoo.com
authors.forename: Adriana
authors.initials: A
authors.lastname: Zámečníkova
authors.forename: Soad
authors.initials: S
authors.lastname: Al Bahar
authors.forename: Ramesh
authors.initials: R
authors.lastname: Pandita
mesh_terms: D000328:Adult; D002871:Chromosome Banding; D002881:Chromosomes, Human, Pair 12; D016044:Fusion Proteins, bcr-abl / Q000235:genetics*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000175:diagnosis / Q000188:drug therapy / Q000235:genetics*; D008297:Male; D014178:Translocation, Genetic
chemical_list: D016044:Fusion Proteins, bcr-abl