BIALLELIC DNA REARRANGEMENTS AND DELETIONS WITHIN THE BCL-6 GENE IN B-CELL NON-HODGKINS-LYMPHOMA

Chromosomal translocations involving band 3q27 are recently described common specific cytogenetic abnormalities in B-cell neoplasms, and the BCL-6 gene, identified on 3q27, was shown to be disrupted and overexp ressed in lymphoma cells having these chromosomal translocations, In t he present study we found rearrangements within the BCL-6 gene in seve n out of 35 cases with B-cell non-Hodgkin's lymphoma (NHL), Further an alysis revealed that three of these patients with BCL-6 abnormality ha d multiple rearranged bands hybridized with probes from a single restr iction fragment within the major translocation cluster (MTC), suggesti ng that independent DNA rearrangements would occur on both alleles, Ad ditionally, Southern blot analysis indicated that three patients carry deletions encompassing the area containing the first exon of the BCL- 6 gene. Our results suggest that biallelic DNA rearrangements and dele tions would occasionally occur in NHL patients with BCL-6 abnormality.