TP53 and Decreased total granulocyte count: Studies describing a role for TP53 in haematopoiesis, specifically the granulocytopenia accompanying overexpression of Trp53 in the Mdm2 knockout mouse9, prompted us to study whether the upregulation of tp53 in mne was in response to cell stress or whether it was due to derepression in the absence of fully functional Zbtb11.