APPLICATION OF FISH TO COMPLEX CHROMOSOMAL REARRANGEMENTS ASSOCIATED WITH CHRONIC MYELOGENOUS LEUKEMIA

Identification of complex chromosomal rearrangements can be difficult, due either to the limited number and sometimes poor quality of metaph ases in bone marrow preparations or to the nature of the rearrangement s. Fluorescence in situ hybridization (FISH) using chromosome-specific DNA libraries in conjunction with a cosmid probe for the c-ABL oncoge ne was performed to substantiate She preliminary G-banded karyotypes o f six patients with chronic myelogenous leukemia (CML). Our results in dicate that FISH is sufficiently sensitive to detect complex and subtl e rearrangements, even in bone marrow preparations with suboptimal met aphases, and can provide valuable corroborative information.