Development of hyperdiploidy starts at an early age and takes a decade to complete

Nearly half of multiple myeloma (MM) patients have hyperdiploidy (HMM) at diagnosis. Although HMM occurs early, the mutational processes before and after hyperdiploidy are still unclear. Here, we used 72 WGS samples from patients with HMM and identified pre and post HMM mutation to define the chronology of development of hyperdipoidy. A MM cell accumulated on median 0.56 mutations per mb pre-HMM and for every clonal pre-HMM mutation, 1.21 mutations accumulated post-HMM. This analysis …