In the context of FIP1L1-PDGFRA-positive MPN with eosinophilia, the concurrent PTPN11 mutation could have amplified downstream signaling, making the leukemic cells less dependent on PDGFRA-driven pathways and more resistant to tyrosine kinase inhibitors like imatinib. The gene discussed is PTPN11; the disease is myeloproliferative neoplasm.