Notably, patients with Smith–Lemli–Opitz syndrome, which is caused by germline mutations in the DHCR7 gene encoding the last enzyme in the de novo cholesterol synthesis pathway, show polycystic kidney (Fitzky et al, 1998; Wassif et al, 1998; Nowaczyk & Irons, 2012). The gene discussed is DHCR7; the disease is polycystic kidney disease.