Dysregulated RET signalling is associated with disease: inactivating mutations of RET lead to a form of neurocristopathy called Hirschsprung’s disease (Amiel et al., 2008), whereas mutations of RET resulting in constitutively active isoforms are associated with several forms of inherited and somatic cancers (Arighi et al., 2005; Borrello et al., 2013). Here, RET is linked to Hirschsprung disease.