Treatment of the Cholesterol Defect in Smith-Lemli-Opitz Syndrome

The purpose of this study is to determine whether supplementation with an oil-based cholesterol suspension will correct the biochemical abnormalities in cholesterol and its precursors in individuals with the Smith-Lemli-Opitz syndrome.

This study involves treating individuals with the Smith-Lemli-Opitz syndrome, a rare inborn error of cholesterol metabolism, with supplemental cholesterol to determine it effects on biochemical sterol metabolites, growth, neuropsychological development, ophthalmologic and auditory function, ERG (electroretinogram) parameters, and CNS metabolites as determined by brain MRS-imaging. Safety of the supplemental cholesterol suspension is monitored by tests of hematologic, renal, and liver function at periodic intervals. There is also a substudy that is investigating potential genotype-phenotype correlations, as well as another that studies biochemical parameters of light sensitivity in cultured skin fibroblasts from affected patients.

200 mg/mL suspension of crystalline cholesterol in oil. Dosage (generally 75-300 mg/kg/day in divided doses) is based on initial cholesterol levels and regulated to increase, yet maintain, cholesterol levels no higher than normal ranges.

Responders was defined as an increase in total serum cholesterol and a decrease in 7-DHC (7-Dehydrocholesterol), and 8-DHC (8-Dehydrocholesterol) were measured on all participants.

Improved neuropsychological development is defined as progressively achieving developmental milestones

Inclusion Criteria: Biochemical confirmation of sterol defect associated with Smith-Lemli-Opitz syndrome Exclusion Criteria: Inability to tolerate crystalline cholesterol Inability to travel to Boston 3-4 times/year based on age

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