FBXW7 and hamartoma: Liver‐specific Fbxw7 deletion in mice results in abnormal proliferation of the biliary system and the development of hamartomas.[11] Although activation of NOTCH signaling has been implicated in the phenotypes observed in mice with Fbxw7 deficiency, the accumulation of any specific NOTCH isoforms, which are known substrates of FBXW7, has not been conclusively demonstrated.