Overexpression of Sloan–Kettering viral oncogene homolog (Ski), a protein which can function both as an oncoprotein and a tumor suppressor gene, leads to increased expression of Shh pathway components, such as Shh, Ptch-1, Smo, Gli1, and Gli2 (Song et al. 2016). The gene discussed is PTCH1; the disease is neoplasm.