As the primary Hh receptor, Ptch1 loss‐of‐function mutations autonomously activate both canonical and non‐canonical signalling, manifesting clinically as Gorlin syndrome (characterised by BCCs and medulloblastomas) [157] and skeletal abnormalities, including craniosynostosis [158] and osteoarthritis [113]. Here, PTCH1 is linked to nevoid basal cell carcinoma syndrome.