Gleevec mainly blocks kinases of the Abl family, but also PDGFR and c-Kit, all of which are implicated in chronic myelogenous leukemia (CML), acute lymphocytic leukemia (ALL), and gastrointestinal stromal tumors (GIST) [9]. This evidence concerns the gene KIT and chronic myelogenous leukemia, BCR-ABL1 positive.