Recently, two fusion genes were described in mesenchymal chondrosarcomas: a recurrent HEY1-NCOA2 found in tumors that had not been cytogenetically characterized and an IRF2BP2-CDX1 found in a tumor carrying a t(1;5)(q42;q32) translocation as the sole chromosomal abnormality.     ///    Chromosome aberrations and HEY1-NCOA2 fusion gene in a mesenchymal chondrosarcoma.. 