FIP1L1/CHIC2/PDGFRA Deletion/Fusion LPH032

Deletion of CHIC2 in patients with idiopathic hypereosinophilic syndrome (HES) and chronic eosinophilic leukaemia (CEL) results in the deletion of CHIC2 and the fusion of FIP1L1(FIP1-like 1) with PDGFRA (platelet derived growth factor receptor alpha) producing a tyrosine kinase which transforms haematopoietic cells. In such patients, this activity is inhibited by imatinib mesylate (Gleevec), which is a tyrosine kinase inhibitor. The diagnosis of the fusion gene therefore, can lead to therapeutic choices for the patient.