Consistent hypereosinophilia >1.5 × 109/l in more than 90% of patients was only observed in association with FIP1L1::PDGFRA and ETV6::ABL1 fusion genes, although we acknowledge an obvious ascertainment bias in that only cases with eosinophilia are routinely screened for distinct TK fusion genes, particularly FIP1L1::PDGFRA. Here, FIP1L1 is linked to Increased total eosinophil count.