There are 2 clinical trials
Smith-Lemli-Opitz Syndrome (SLOS) is a genetic disorder (autosomal recessive) caused by an
abnormality in the production of cholesterol. The disorder can occur in both a "mild" or
"severe" form. SLOS is associated with multiple birth defects and mental retardation. Some of
the birth defects include; abnormal facial features, poor muscle tone, poor growth, shortened
life span, and abnormalities of the heart, lungs, brain, gastrointestinal tract, limbs,
genitalia, and kidneys.
There is no known cure for SLOS but recently patients have been treated with increased
amounts of cholesterol in their diet. The cholesterol in a persons diet is unable to correct
the abnormalities in the patient's organs, but researchers hope it will improve growth
failure and mental retardation.
This study was developed to answer questions about the causes and complications of SLOS, as
well as the effectiveness of cholesterol treatment. The study will enroll patients diagnosed
with SLOS, and their mothers. The objectives of the study will be to address the following
One SLOS mutant allele (R404C) appears to be present in individuals of French Canadian and Creole heritage. --- R404C ---
Description: StabilizationMeasure: Neurocognitive testing Time: yearly
RSH/Smith-Lemli-Opitz syndrome (SLOS) is one that causes mental retardation. It is common in the Caucasian population but rare in African American and African black populations. It has been shown that SLOS is caused by a specific defect in DHCR7, an enzyme used in cholesterol metabolism. Studies have already been done to determine the frequency of the SLOS-causing mutations in various geographic Caucasian populations. This study will investigate the frequency of the DHCR7 mutations in the African American population. If the frequency observed suggests that SLOS cases are not being identified in this ethnic group, the study will provide the rationale for future studies to identify these patients. The sample size will be 1,600. The study population will consist of archived biological specimens in the form of newborn screening blood spots from two newborn screening centers, one in Maryland and one in Pennsylvania. Subjects will be of African American ethnicity, including blacks of African, Caribbean, and Central American descent. Genomic DNA will be extracted from blood spots and screened for the six common SLOS mutations. If SLOS syndrome is found, followup will be attempted for the Maryland samples (the Pennsylvania samples will be totally anonymous).
In these Caucasian populations, the most common mutations (IVS8-1G>C, W151X, V326L, R352W, R404C and T93M) account for 60% of SLOS mutant alleles. --- V326L --- --- R352W --- --- R404C ---