Alterations frequently associated with CH, such as in JAK2 (specifically, V617F; n = 4 cases), ATM (n = 44 alterations in 34 cases), and CHEK2 (n = 46 alterations in 36 cases; Supplementary Data 9), were also observed to be unique to LBx in our cohort, albeit rare. Here, CHEK2 is linked to cyclic hematopoiesis.