Recent research into the use of serum exosomes for diagnosis and prognosis of leukemia has produced promising results, with findings that exosomal TGF-β1 levels and relative levels of the three TGF-β1 forms (TGF-β1 pro-peptide, latency-associated peptide (LAP), and mature TGF-β1) were distinct in AML patients in different stages of chemotherapy [22], and that a grading system based on exosomal levels of miR-150, miR-155, miR-221 and miR-1246 was able to effectively distinguish AML cell xenografted mice from control mice [61]. The gene discussed is TGFB1; the disease is leukemia.