RSH/SLO ("Smith-Lemli-Opitz") syndrome: historical, genetic, and developmental considerations.

Thirty years after the publication of Smith et al. [1964: J Pediatr 64:210-217] of 3(4) cases of the RSH/SLO ("Smith-Lemli-Opitz") syndrome and after the publication by Roux [1964: Arch Franç Pédiatr 21:451-464] on the teratogenic action of Triparanol, a defect of cholesterol metabolism was discovered by Tint and his co-workers in the blood of the patients of Irons and Elias [Irons et al., 1993: Lancet 341:1414]. In this manner, the RSH syndrome has been identified as another metabolic multiple congenital anomalies/mental retardation (MCA/MR) syndrome (prototype Zellweger syndrome) in which deficient cholesterol synthesis must be held responsible for all parts of the syndrome, including blastogenetic and organogenetic malformations, minor anomalies, more or less severe abnormalities of CNS and PNS structure and function, postnatal failure to thrive, and, in some cases, stillbirth or infancy/childhood death.