Patterns and Frequencies of Acquired and Constitutional Uniparental Isodisomies in Pediatric and Adult B-Cell Precursor Acute Lymphoblastic Leukemia.

Summary, in English

Single nucleotide polymorphism (SNP) arrays are increasingly being used in clinical routine for genetic analysis of pediatric B-cell precursor acute lymphoblastic leukemias (BCP ALL). Because constitutional DNA is not readily available as a control at the time of diagnosis, it is important to be able to distinguish between acquired and constitutional aberrations in a diagnostic setting. In the present study we focused on uniparental isodisomies (UPIDs). SNP array analyses of 143 pediatric and 38 adult B-cell precursor acute lymphoblastic leukemias and matched remission samples revealed acquired whole chromosome or segmental UPIDs (wUPIDs, sUPIDs) in 32 cases (18%), without any age- or gender-related frequency differences. Acquired sUPIDs were larger than the constitutional ones (mean 35.3 Mb vs. 10.7 Mb; P<0.0001) and were more often terminally located in the chromosomes (69% vs. 4.5%; P<0.0001). Chromosomes 3, 5, and 9 were most often involved in acquired wUPIDs, whilst recurrent acquired sUPIDs targeted 6p, 9p, 9q, and 14q. The majority (56%) of sUPID9p was associated with homozygous CDKN2A deletions. In pediatric ALL, all wUPIDs were found in high hyperdiploid (51-67 chromosomes) cases and an extended analysis, also including unmatched diagnostic samples, revealed a higher frequency of wUPID-positivity in higher modal number (56-67 chromosomes) than in lower modal number (51-55 chromosomes) high hyperdiploid cases (34% versus 11%; P=0.04), suggesting different underlying mechanisms of formation of these subtypes of high hyperdiploidy. This article is protected by copyright. All rights reserved.

• Author: Kristina Lundin; Linda Olsson; Setareh Safavi; Andrea Biloglav; Kajsa Paulsson; Bertil Johansson
• Department/s: Division of Clinical Genetics; BioCARE: Biomarkers in Cancer Medicine improving Health Care, Education and Innovation
• Publishing year: 2016-01-16
• Language: English
• Pages: 472-479
• Publication/Series: Genes, Chromosomes and Cancer
• Volume: 55
• Issue: 5
• Full text: - 4 MB; Download statistics
• Links: http://www.ncbi.nlm.nih.gov/pubmed/26773847?dopt=Abstract; http://dx.doi.org/10.1002/gcc.22349
• Document type: Journal article
• Publisher: John Wiley & Sons Inc.
• Topic: Cancer and Oncology
• Status: Published
• ISBN/ISSN/Other: ISSN: 1045-2257