Cholesterol supplementation enhances growth of phallus in Smith-Lemli-Opitz syndrome

Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive inborn error of cholesterol biosynthesis due to a deficiency of the last enzyme of the cholesterol synthetic pathway, 7-dehydrocholesterol reductase. Affected patients have low concentrations of cholesterol and elevation of the cholesterol precursor, 7-dehydrocholesterol (7-DHC). Multiple congenital anomalies, dysmorphic facies, and growth and developmental retardation are common. Severely affected males have ambiguous genitalia. We believe that the genital anomalies seen in affected males are due to deficiency of androgens, but this has never been proven.