WDLPS and DDLPS share the cytogenetic abnormality, specifically amplification of the 12q13-15 region that leads to subsequent diagnostic amplification of MDM2 and CDK4. Previous cytogenetic studies have identified alternative amplification of 1p32 and 6q23 in DDLPS and not identified in WDLPS. This evidence concerns the gene MDM2 and dedifferentiated liposarcoma.