CYTOGENETIC AND MOLECULAR ANALYSIS OF 6Q-DELETIONS IN BURKITTS-LYMPHOMA CELL-LINES

Although abnormalities of chromosome 6 have frequently been observed i n Burkitt's lymphoma (BL), they have so far not been defined by modern cytogenetic and molecular methods. By a combination of high-resolutio n chromosome banding, fluorescence in situ hybridization (FISH), and l oss of heterozygosity (LOH) analysis, we have examined the nature of a berrations affecting chromosome 6 in 7 previously established BL cell lines. All cell lines exhibited the characteristic translocations asso ciated with BL; 5 had t(8;14)(q24;q32) and 2 had t(8;22)(q24;q11). Thr ee cell lines had deletions of 6q; 3 others had rearrangements affecti ng 6q, whereas one cell line had apparently normal chromosomes 6. FISH analysis of the three deletions established that they were interstiti al. LOH analysis with probes mapped to the 6q26-27 region confirmed th e sub-telomeric interstitial deletion in cell line BL-108, which had a del(6)(q23q27). All informative loci mapped to 6q26-27 (5/7) were del eted in BL-74, which had no apparent cytogenetic abnormality in chromo some 6, thus documenting a sub-microscopic deletion. These data define the cytogenetic and molecular limits of 6q deletions in BL and are co nsistent with our previous demonstration of LOH analysis of the site o f a candidate tumor suppressor gene in the 6q25-27 region. (C) 1994 Wi ley-Liss, Inc.