Evolution over time of the JAK2V617F mutational burden. The percentage JAK2V617F value represents the ratio of JAK2V617F mutated DNA to all JAK2 DNA present in a sample as measured by quantitative polymerase chain reaction. The 2 arrows above the graph represent the first and second allogeneic transplantations. Donor samples (○) are connected with a dashed-pointed line, recipient peripheral blood samples (■) are connected with a full line, and recipient bone marrow samples () are connected by a dashed line.