Cib1 deletion increases megakaryocyte ploidy in response to exogenous TPO. (A) Representative histograms of CD41⁺ BM cells from WT and Cib1^−/− mice after addition of 50 ng/mL TPO for 24 hours. (B) Quantification of megakaryocyte ploidy from panel A. *P < .05 vs WT (n = 7). (C) Representative histograms of CD41⁺ BM cells from WT and Cib1^−/− mice after 50 ng/mL TPO treatment for 5 days. (D) Quantification of megakaryocyte ploidy from panel C. *P < .05 vs WT (n = 6).