<unk>  is an metabolic and developmental disorder that occurs due to deficiency of 7-dehydrocholesterol reductase.  7-dehydrocholesterol reductase is an enzyme required for the formation of cholesterol from 7-dehydrocholesterol.
Smith-Lemli-Opitz syndrome
Smith–Lemli–Opitz syndrome
Smith-Magenis syndrome
Ellis-van Creveld syndrome
Landau-Kleffner syndrome
Rabson-Mendenhall syndrome
Lawrence-Moon syndrome
Abderhalden-Kaufmann-Lignac syndrome