The chromosome 11q23 band is a genetic region frequently involved in nonrandom karyotypic abnormalities of acute leukemia. A genomic locus named ALL-1 or MLL, where 11q23 breakpoints are clustered, has been recently cloned and characterized. We have made use of an ALL-1-specific probe in Southern blot experiments to analyze the configuration of this gene in a large series of acute leukemia pati...

DNA rearrangements caused by chromosometranslocations between band 11q23 and various chromosomes can be detected by a single probe, B859, an 859-base pair complementary DNA fragment derived from the human ALL-i gene. To try to understand why band 11q23 becomes a frequent target ofthe translocatlons,we have sequencedthe entire break point cluster region, a 8342-base pair BamHI genomic fragment d...

Chromosome band 11q23, the location of the HRX gene, is a site of recurrent translocations in human malignancies. Infants with acute lymphoblastic leukemia (ALL) commonly have 11q23 translocations and have an especially poor prognosis despite intensive chemotherapy. We analyzed 96 cases of infant ALL treated on three consecutive Pediatric Oncology Group protocols to determine the frequency and ...

To study prognostic factors in infant acute myeloid leukemia (AML), we analyzed 44 children treated on Childrens Cancer Group protocols for MLL gene rearrangement by Southern blot, cytogenetic 11q23 abnormalities, and reactivity with monoclonal antibody 7.1. This antibody detects the human homologue of the rat NG2 chondroitin sulfate proteoglycan molecule, which has previously been reported to ...

Microsatellites are important highly polymorphic genetic markers dispersed in the human genome. Using a panel of 22 (CA)n repeat microsatellite markers mapped to recurrent breakpoint cluster regions specifically involved in leukemia, we investigated 114 adult leukemias (25 acute lymphocytic leukemia [ALL], 32 acute myeloid leukemia [AML], 36 chronic lymphocytic leukemia [CLL], and 21 chronic my...

down’s syndrome, or 21 trisomy, is the most common autosomal abnormality, with incidence of 1 per 815 live births in iran. worldwide reports indicate that about 95% are regular trisomy, or nondisjunction, 1% are mosaic and 4% due to translocation. however, these values show a geographical variation. a cytogenetic study of down's syndrome, or trismoy 21, was carried out on 366 cases (202 males a...

Therapy-related acute myeloid leukemias with balanced translocations affecting the 11q23 chromosome region are one of the most serious complications of treatments with topoisomerase II inhibitor drugs as epipodophillotoxins and anthracyclines. 1,2-5 These cases are usually associated with short interval time from previous chemotherapies, absence of myeloid dysplastic phase, hyperleukocytosis an...