Metaphase FISH on four cases regarding the involvement of the HMGA2 gene. BAC clones RP11-299L9 (FITC) and RP11-427K2 (Cy3), spanning the 5' and 3' parts, respectively, of HMGA2 were used. Arrowheads indicate normal chromosomes 12 A) Lipoma (case 10) with a t(5;12)(q33;q14) where the entire HMGA2 locus was translocated to chromosome 5. A wcp5 probe was used to identify chromosome 5 in tumor cells. The derivative chromosome 12 was present in the metaphase cell, but not included in the picture B) Atypical lipoma (case 55) with ring chromosome and amplification and split signal of HMGA2. Normal signals for HMGA2 can be seen on the two normal chromosomes 12. C) Lipoma (case 11) with an inv(12)(q14q24) causing a deletion of the 3'-end of HMGA2; thus, only the green signal corresponding to RP11-299L9, covering the 5'-part, can be seen. D) Lipoma (case 14) with a t(10;12)(q22;q15) resulting in a split signal for HMGA2; the 3' part of the gene is translocated to chromosome 10. A wcp12 was used to identify chromosome 12 in tumor cells.