Involvement of ID4 in the translocation, t(6;14)(p22;q32). (A) Diagram showing the location of clones used in the dual-color, dual-fusion FISH probe and breakpoints cloned by LDI-PCR from IGHJ6 segments. (B) Partial G-banded karyotype showing normal and derived copies of chromosomes 6 and 14. The normal copies of each chromosome are on the left and the rearranged copies are denoted by arrows showing the breakpoints. (C) Metaphase chromosomes hybridized with clones RP11-377N20 (Spectrum green) and RP3-498I24 (Spectrum red). Two red/green fusion signals are shown, one located on the normal chromosome 6 (red arrow) and the other on the derived chromosome 6 (yellow arrow). A red signal is seen on the derived chromosome 14 (green arrow) indicating that the breakpoint is located within RP3-498I24 close to ID4. Image was acquired by staining with DAPI (Vector Laboratories, Burlingame, CA), with a Zeiss Axioskop microscope (Zeiss, Welwyn Garden City, United Kingdom) fitted with a 100× oil objective, a CCD camera (Applied Imaging, Newcastle, United Kingdom), and MacProbe image acquisition version 4.3 software (Applied Imaging). (D) Nucleotide sequences of the ID4-IGHJ junctions. Vertical lines show nucleotide identity. IGHJ segments are shown in boldface letters. Patient 2817 had an inverted fragment froms IGHJ2-3 prior to IGHJ4 segment.