Chromosome 14 copy number-dependent IGH gene rearrangement patterns in high hyperdiploid childhood B-cell precursor ALL: implications for leukemia biology and minimal residual disease analysis

E Csinady, Vincent van der Velden, R Joas, S Fischer, Jeltje Vries, Berna Beverloo, M Konig, U Potschger, Jacques Dongen, G Mann, OA Haas, ER Panzer-Grumayer

Research output: Contribution to journalArticleAcademicpeer-review

9 Citations (Scopus)

Abstract

Childhood B-cell precursor acute lymphoblastic leukemia (BCP ALL) is generally a clonal disease in which the number of IGH rearrangements per cell does not exceed the number of the IGH alleles on chromosome 14. Consequently, monoclonal high hyperdiploid (HeH) cases with a trisomy 14 can harbor three rearrangements, a pattern that otherwise may be misinterpreted to be oligoclonal. Oligoclonal IGH rearrangements, on the other hand, may be instable at relapse and should therefore not be used for minimal residual disease analysis. We thus investigated the association between IGH allele copy numbers and the IGH rearrangement patterns in 90 HeH BCP ALL with either two (13%) or three copies (87%) of chromosome 14. HeH cases (44%) had an oligoclonal IGH rearrangement pattern, but true oligoclonality-after correction for the respective copy number of IGH alleles-was only 16%. Monoclonal and oligoclonal HeH cases had predominantly V-H to preexisting DJ(H) recombinations, a finding that contrasts with oligoclonal cases of other major genetic BCP ALL subgroups in which V-H replacements prevail. We conclude that for the precise assessment and correct interpretation of clonality patterns in BCP ALL, the IGH allele copy number has to be taken into consideration. Leukemia (2009) 23, 870-876; doi:10.1038/leu.2008.390; published online 15 January 2009
Original languageUndefined/Unknown
Pages (from-to)870-876
Number of pages7
JournalLeukemia
Volume23
Issue number5
DOIs
Publication statusPublished - 2009

Cite this