Myeloid (and lymphoid) neoplasms with eosinophilia are associated with rearrangement of the tyrosine kinase (TK) genes, namely PDGFRB, PDGFRA, FGFR1, JAK2, FLT3, and ABL1 (excluding BCR-ABL1). This evidence concerns the gene FLT3 and Increased total eosinophil count.