Typical applications include detecting subclonal pathogenic mutations in driver genes such as NRAS/KRAS in leukemias that frequently seed relapse [2], mosaic cancer predisposition mutations [3, 4], age-related clonal hematopoiesis [5] that increases cancer risk, and liquid biopsy for non-invasive diagnosis and disease monitoring [6–9]. The gene discussed is NRAS; the disease is cancer.