The successful induction of tumours with similar properties to human ACP established that targeting RP progenitors with oncogenic β-catenin is sufficient to form tumours; hence, CTNNB1 mutations are drivers of ACP tumourigenesis in mouse and humans (Gaston-Massuet et al. 2011, Martinez-Barbera 2015, Martinez-Barbera & Andoniadou 2016). This evidence concerns the gene CTNNB1 and neoplasm.