Chin and colleagues used detailed mutational analysis of aged mice and transplantation to evaluate the mouse as a model of clonal hematopoiesis (CH). Their data suggest that while murine hematopoietic stem cells acquire mutations in CH-associated genes when aged and CH clones can expand after transplantation (as in humans), these are rare events. Nevertheless, genetically manipulated murine models mimicking human CH are feasible and may prove useful in the future.