2006; Ryan et al. 2006; Swaminathan & Tsygankov 2006; Meyer et al. 2011). Loss of c‐CBL led to development of mastocytosis in transgenic mice associated with defective ubiquitination and subsequent accumulation of KIT and disrupted signalling (Bandi et al. 2009; Orinska et al. 2010). KIT expression and signalling was also found in human acute myeloid leukaemia cells with c‐Cbl mutations (Makishima et al. 2012). Here, CBL is linked to mastocytosis.