Dr Valk’s main interest is unraveling the molecular heterogeneity of hematologic malignancies, in particular acute myeloid leukemia (AML). Using various genome-wide technologies, such as gene expression profiling, genotyping and next generation sequencing, Dr Valk revealed novel insights into the heterogeneity and biology of AML. His work has developed molecular biomarkers that are incorporated into routine risk-stratification and clinical care of AML patients. More recently Dr Valk has focused on the detection of molecular minimal residual disease In AML, clonal hematopoiesis and germline predisposition to myeloid malignancy.