In four lipomas, exons 1–3 of HMGA2 were fused to a sequence of SETBP1 (cases 4, 7 and 8) or an intragenic sequence from 18q12.3 (case 3) 10 kbp distal to SETBP1. In one tumor (case 5), the translocation t(12;18) resulted in fusion of exons 1–4 of HMGA2 with an intronic sequence of GRIP1 which also maps to chromosome band 12q14.3. The gene discussed is HMGA2; the disease is lipoma.