AbstractWe previously reported a 5′ rearrangement of theBCL2locus in a t(18;22) variant translocation found in a lymphocytic lymphoma. Primary structure analysis of both rearranged chromosomes confirmed the localization of the breakpoint in the so‐called vcr region (for variant cluster region) that encompasses Z‐DNA stretches 5′ of theBCL2locus, and in between Jλ1 and Cλ1 segments on theIGLlocus. A 1,027 nucleotide segment from chromosome 22 was repeated on both derivative chromosomes 18q + and 22q ‐. This segment contained an octanucleotide that was also present in the normal chromosome 18 close to the breakpoint. As a consequence of the translocation, a normal‐sized BCL2 transcript was overexpressed in tumor cells. © 1993 W