Fluorescence in situ hybridization confirmation of 5q deletions in patients with hematological malignancies

Fluorescence in situ hybridization (FISH) using specific probes for the 5q3 1 similar to 32 region and a whole chromosomal painting (WCP) probe for chr omosome 5 were used to corroborate the results of classical cytogenetic exa minations performed on G-banded chromosomes of 77 patients with hematologic al malignancies. Using classical cytogenetic methods, we suspected the pres ence of clones with a deletion 5q in 63 patients, and complex rearrangement s with involvement of chromosome 5 in 14 other cases. Fluorescence in situ hybridization proved the occurrence of deletion 5q31 in 23 patients and asc ertained translocations of part of the long arms of deleted chromosome 5 wi th missing region 5q31 in 12 patients. In 2 cases, the 5q31 region was tran slocated to other chromosomes as a part of complex rearrangements. The comb ination of classical cytogenetics and FISH with specific probes for the 5q3 1 band yielded cytogenetic results in 35 cases. Routine FISH detection of d eleted regions was possible by commercially available cosmid probes for the 5q31 chromosomal band. The interpretation of small deletions and frequent involvement of the deleted chromosomes 5 in complex translocations were asc ertained by WCP probes. (C) Elsevier Science Inc., 2000, All rights reserve d.