Monosomic loss of MIR15A/MIR16-1 is a driver of multiple myeloma proliferation and disease progression.

The most common genetic abnormality in multiple myeloma (MM) is the deletion of chromosome 13, seen in almost half of newly diagnosed patients. Unlike chronic lymphocytic leukemia, where a recurrent minimally deleted region including has been mapped, the deletions in MM predominantly involve the entire chromosome and no specific driver gene has been identified. Additional candidate loci include and , but while biallelic deletion of is associated with disease progression, is a common essential gene and complete inactivation is not observed. The VkMYC transgenic mouse model of MM spontaneously acquires del(14), syntenic to human chromosome 13, and complete inactivation, but not mutations. Taking advantage of this model, we explored the role in MM initiation and progression of two candidate loci on chromosome 13: . Monoallelic deletion of but not was sufficient to accelerate the development of monoclonal gammopathy in wildtype mice, and the progression of MM in VkMYC mice, resulting in increased expression of target genes and plasma cell proliferation, which was similarly observed in patients with MM.