(4) Patients with CEL carried the FIP1L1-PDGFRA fusion gene and TCR gamma rearrangement concurrently, their relationship warrants further study..     ///    Detection of the FIP1L1-PDGFRA fusion gene was performed by nested RT-PCR.     ///    The FIP1L1-PDGFRA fusion gene positivity in bone marrow mononuclear cells in 12 cases was identified. 