Genetics and Clinical Characteristics of Bardet-Biedl Syndrome
Stopped early
Conditions studied: Bardet-Biedl Syndrome
In brief
This study will evaluate patients with a rare inherited condition called Bardet-Biedl syndrome . The purpose of the study is to learn more about the genetics and clinical characteristics of this disorder. Patients may have the following problems: polydactyly (extra fingers and toes); retinal dystrophy (changes in the retina that may lead to vision problems, including blindness); obesity and diabetes (overweight and high blood sugar due to failure of body organs to respond to insulin); cognitive dysfunction (difficulties with learning and understanding); hypogenitalism (decreased functioning of the ovaries in women and the testes in men); kidney anomalies (changes in the structure or function of the kidneys); heart disease; and hepatic fibrosis (liver disease). Patients with Bardet-Biedl syndrome may be eligible for this study. First-degree relatives will also be enrolled for certain tests and procedures. Candidates are screened with a review of their medical records, laboratory tests, and x-rays. Patients in this study undergo the following tests and procedures: * Medical and family history and physical examination, including body measurements. * Blood tests to evaluation kidney, liver, heart, and hormonal function, and for genetic studies and other research purposes. * Dual emission x-ray absorptiometry (DEXA) scan to measure the amount of total body fat. For this test, the subject lies on a table for scanning with low-dose X-rays. * Computed tomography (in adults) of the abdomen to measure abdominal fat. CT uses a small amount of radiation to obtain images of internal body structures. * Magnetic resonance imaging (in children) of the abdomen to measure abdominal fat. MRI uses a magnetic field and radio waves to obtain images of internal body structures. * Oral glucose tolerance tests to measure blood glucose and insulin levels. For this test, the patient drinks a glucose (sugar) solution. Blood samples are drawn through an IV catheter before the test begins and at 1, 2, and 3 hours after drinking the solution. * Complete eye examination to look for retinal changes and to assess vision, and, if medically needed, an examination of the ear, nose, and throat to check for hearing and breathing abnormalities. * Tests of learning ability in patients over 5 years of age. For younger patients, a parent is asked about the child's development. * Ultrasound study of the ovaries and uterus in females and of the testes in males. * Photographs of the face, hands, feet, body, and genitalia, if the patient agrees. * Meeting with investigators and a genetic counselor for review of test findings when the studies are completed. Relatives of patients have a complete medical and family history and physical examination. Blood is drawn for assessment of kidney, liver, heart, and hormonal function and for genetic study and other research purposes. Relatives over 5 years of age may have tests of learning ability and cognition. For younger patients, a parent is asked about the child's development. Relatives meet with investigators and a genetic counselor for review of test findings when the studies are completed.
Key facts
- Study ID
- NCT00078091
- Run by
- National Human Genome Research Institute (NHGRI)
- People needed
- 194
- Starts
- 2004-02-17
- Expected to finish
- 2016-02-05
- Last updated by the study team
- 2019-12-04
Who can join
Age: any. Sex: any. Healthy volunteers: not accepted.
You may not qualify if…
- Neither healthy volunteers unrelated to an affected patient nor lab personnel will be enrolled.
- We will make efforts to obtain consent from all parents/guardians of minor subjects (i.e. we would not allow a single parent to consent a child when both parents have parental rights). If a single parent or guardian has sole custody/legal responsibility for a child (e.g., a divorce with full custody to one parent or one parent is deceased), we will accept consent from one parent.
- Both mothers and fathers of children with BBS (who are also typically enrolled in our protocol, as described above) are eligible to participate in the interview portion of the study. We hypothesize that mothers and fathers will, as groups, have slightly different experiences with coping with courtesy stigma, although a couple may have convergent beliefs, coping mechanisms, and experiences. As such, we predict that we will initially conduct interviews with both parents of the same proband (assuming both parents are interested in participating), although we may target either mothers or fathers only following interim analysis of the interview transcripts.
Where it is running
- National Institutes of Health Clinical Center, 9000 Rockville Pike — Bethesda, Maryland, United States
Full record on ClinicalTrials.gov
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