Heterogeneous TCR delta V delta 2-D delta 3 rearrangements and their relation to IgH and TCR gamma gene status in childhood B cell precursor leukaemias

In this study we aimed to test the hypothesis that leukaemias with oligoclo nal V delta 2-D delta 3 rearrangements are clonal at the IgH and TCRG gene status and that the oligoclonality is a poor prognostic marker. In ten leuk aemias the individual V delta 2-D delta 3 rearrangements characterised diff erent populations as deduced from single cell analysis and/or from densitom etric differences of PCR products. Five of these leukaemias were clonal by the IgH and/or TCRG gene status. We therefore conclude that ALL is a clonal disease despite the presence of heterogeneous TCRD rearrangements. Our cli nical data show that oligoclonality at the TCRD level does not represent an adverse prognostic factor. (C) 1999 Elsevier Science Ltd. All rights reser ved.