View clinical trials related to Genetic Diseases, X-Linked.
Filter by:This study will evaluate the safety and effectiveness of simvastatin in treating children with Smith-Lemli-Opitz syndrome (SLOS). Patients with this inherited disease are deficient in an enzyme that converts a substance called 7-dehydrocholesterol (7-DHC) to cholesterol. Cholesterol synthesis is impaired, causing birth defects and mental retardation. This study will examine whether simvastatin can increase the amount of the deficient enzyme, thereby lowering 7-DHC and increasing cholesterol. It will examine the safety of simvastatin in affected children and its effects on their behavioral problems. Children between 4 and 18 years of age with mild to typical SLOS may be eligible for this study. Participants will be evaluated at the NIH Clinical Center in Bethesda, MD, and at the Kennedy Krieger Institute in Baltimore, MD, upon admission to the study and again at 6, 12, 20, and 26 months. The visits will last 3 to 4 days, and will include a medical history and physical examination, photographs to document medical findings, and other procedures detailed below. In addition, blood samples will be collected at 1, 3, 9, 14, 15, 17, and 23 months. Parents will complete several questionnaires during the study. Procedures include the following: - Simvastatin and cholesterol supplementation therapy. Patients take cholesterol supplements (50 milligrams per kilogram per day) plus simvastatin (0.5 mg/kg/day for 6 weeks and then 1 mg/kg/day) for 12 months, and cholesterol supplements plus a placebo for 12 months. - Blood draws to check liver, muscle, and kidney function, hormone levels, vitamin D levels, blood counts, cholesterol and 7-DHC levels, and lipoprotein levels. Some extra blood is drawn for research purposes. - Urine collection. Urine is collected using a toilet hat. For children who are not toilet trained, urine is collected in a bag taped to the skin with an adhesive. - Electroretinogram (ERG) to measure the function of the retina, the light-sensitive tissue at the back of the eye. ERG is done under sedation. After adapting the child's eyes to the dark, an electrode is taped to the child's forehead, the surface of one eye is numbed with eye drops, and a contact lens is placed on the eye. The child looks inside a globe that emits a series of light flashes. The contact lens senses electrical signals generated by the retina when the light flashes. After the ERG, the patient has a full eye exam, including pupil dilation and photographs of the eye. - Lumbar puncture (spinal tap) to collect a sample of cerebral spinal fluid (CSF). This procedure, done while the patient is sedated for the ERG, shows whether simvastatin affects brain cholesterol and chemical levels. Under local anesthetic, a needle is inserted in the space between the bones in the lower back where the CSF circulates below the spinal cord. A small amount of fluid is collected through the needle. - CRH stimulation test to detect hormone-related problems in cholesterol synthesis. The patient is given CRH, a hormone involved in cholesterol synthesis, through a plastic tube placed in a vein. Blood samples are collected through the same catheter to measure levels of other hormones involved in cholesterol production. - Electroencephalogram (EEG) to look at the electrical activity (brain waves) of the child's brain. - Activity monitoring. An activity monitor, which looks like and is worn like a watch, is used to record the child's level of activity for a 48-hour period. - Urine pregnancy test at every visit for female patients over age 10. - Skin swab for sterol (solid alcohol, such as cholesterol) analysis. An alcohol pad is rubbed lightly against the child's arm or thigh to collect skin cells. - Stool collection. A small stool sample is collected from the child's diaper or, for children who are toilet trained, from a toilet "hat" like that used to collect urine.
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).
OBJECTIVES: I. Provide curative immunoreconstituting allogeneic bone marrow transplantation for patients with primary immunodeficiencies. II. Determine relevant outcomes of this treatment in these patients including quality of survival, extent of morbidity and mortality from complications of the treatment (e.g., graft versus host disease, regimen related toxicities, B- cell lymphoproliferative disease), and completeness of functional immunoreconstitution.
OBJECTIVES: I. Examine the intestinal absorption of dietary cholesterol in patients with Smith-Lemli-Opitz syndrome. II. Measure the effect of dietary cholesterol on plasma sterol composition. III. Quantify basal cholesterol synthesis, turnover of cholesterol and 7-dehydrocholesterol, and the effects of dietary cholesterol on these parameters. IV. Identify fecal bile acid excretion quantitatively and qualitatively in these patients. V. Compare the incorporation of deuterated water into plasma cholesterol, 7-dehydrocholesterol, and other intermediates, and assess the effect of dietary cholesterol on this incorporation.
OBJECTIVES: I. Identify the molecular defects responsible for primary immunodeficiency disorders. II. Explore the mutations within each syndrome to better understand the genetics of these disorders. III. Study the function of the Wiskott-Aldrich syndrome proteins (WASP). IV. Design methods to identify carriers and for prenatal diagnosis. V. Explore new avenues for therapy.
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 questions: 1. <TAB> What is the prognosis / natural history of the demyelination in the nervous system of patients with SLOS? 2. <TAB> Do patients with SLOS have other problems concerning the function of their endocrine systems? 3. <TAB>What are the genetic make-ups of patients with SLOS? 4. <TAB>Can further studies of cholesterol metabolism and genetic testing, using SLOS fibroblasts, increase the understanding of SLOS?<TAB>...
The research goal of this study is to obtain CD34+ hematopoietic stem cells (HSC) from peripheral blood and/or bone marrow, and Mononuclear Cells (lymphocytes and monocytes), and granulocytes (grans) from peripheral blood that will be used in the laboratory and/or in the clinic to develop new cell therapies for patients with inherited or acquired disorders of immunity or blood cells. Development of novel cellular therapies requires access to HSC, Mononuclear Cells and/or granulocytes as the essential starting materials for the pre-clinical laboratory development of gene therapies and other engineered cell products. HSC or blood cells from healthy adult volunteers serve both as necessary experimental controls and also as surrogates for patient cells for clinical scale-up development. HSC or blood cells from patients serve both as the necessary experimental substrate for novel gene therapy and cellular engineering development for specific disorders and as pre-clinical scale up of cellular therapies. Collection of cells from adult patients collected in the NIH Department of Transfusion Medicine (DTM) under conditions conforming to accepted blood banking clinical practice may also be used directly in or cryopreserved for future use in other NIH protocols that have all required regulatory approvals allowing such use. In summary, the research goal of this protocol is the collection of HSC or blood cells that may be used for both laboratory research and/or for clinical treatment in other approved protocols.