The loss of cytochrome P450 family 27 subfamily A member 1 (CYP27A1), which catalyses the rate-limiting hydroxylation of cholesterol to bile acid, has been reported to contribute to the dysregulation of cholesterol homeostasis in PCa [239] and to be associated with shorter disease-free survival and higher tumour grade. The gene discussed is CYP27A1; the disease is posterior cortical atrophy.