The observation that QPD dysregulates PLAU but not C10orf55 (the other duplicated gene) in megakaryocytes, and that QPD increases production of normal PLAU transcripts from the disease chromosome in megakaryocytes [1], provides further evidence that a megakaryocyte specific defect that selectively upregulates PLAU transcript levels underlies the pathogenesis of QPD. The gene discussed is C10orf55; the disease is Quebec platelet disorder.