Our vision, that of the researchers at the University of Texas Health Science Center at San Antonio, is that every person with a chromosome 18 abnormality will have an autonomous and healthy life. Our mission is to provide families affected by chromosome 18 abnormalities with comprehensive medical and educational information. Our goals are to provide definitive medical and education resources for the families of individuals with chromosome 18 abnormalities; perform and facilitate groundbreaking clinical and basic research relating to the syndromes of chromosome 18; and to provide treatments to help these individuals overcome the effects of their chromosome abnormality.
Protocol Summary: The hypotheses are: 1. growth hormone (GH) deficiency in children with chromosome 18 deletions is accompanied by cognitive and microstructural abnormalities of the brain that can be ameliorated by GH treatment; and 2. the physical and behavioral findings in individuals with abnormalities of chromosome 18 are due to the genes that present in a non-diploid number. Therefore, correlation of the physical and behavioral findings with the extent of the deletion will help identify the genes involved. An understanding of the molecular mechanisms of the phenotype will provide the insight necessary to devise appropriate therapies. Our goals are: 1. to be the international medical and education resource for the families of individuals with chromosome 18 abnormalities; 2. to perform and facilitate both clinical and basic research relating to the disorders of chromosome 18; and 3. to devise treatments to help these individuals overcome the negative effects of their chromosome abnormality. To attain these goals, the study has the following specific aims: 1. perform genotypic molecular analysis on the DNA of the subjects and their biological parents to determine the genotype of the affected individual; 2. gather comprehensive clinical data on individuals with chromosome 18 abnormalities including: 1. determination of growth hormone levels; 2. measurement of corticotrophin, thyroid and sex hormones; 3. psychiatric and neuropsychological evaluations; 4. audiology and ENT testing; 5. brain MRI scan; 6. genetic dysmorphology examination; 7. neurology exam; 8. dental exam; 9. speech pathology evaluation; 10. gastrointestinal exam; 11. orthopedic exam; 12. ophthalmology exam. The phenotypical assessment will be longitudinal; therefore, the participants will have a wide age range. This extensive range plus the fact that some participants will be assessed multiple times means that not all components of the clinical studies will be appropriate for every subject at every visit.
Study Type
OBSERVATIONAL
Enrollment
4,000
Growth hormone stimulating testing using Arginine and Clonidine, Corticotrophin releasing hormone stimulation test
Gonadotrophin releasing hormone stimulation test Thyroid testing - T4, TSH, T3 uptake, and anti-thyroidal antibodies baseline sample - no medication administered
evaluation by neuropsychologist, standardized testing geared to study participant's age, abilities and past medical history
neurotological exam, behavioral audiometry, immittance audiometry, assessment of the function of the inner ear using otoacoustic emissions, Auditory brain responses
MRI of the brain - standard clinical procedure
Genetic evaluation with picture and measurements, physical exam
physical examination including observation of balance, coordination and reflexes.
Visual detal inspection with panorex X-ray of the entire mouth
Standardized speech \& language tests and naturalistic assessment procedures.
Psychiatric interview about history of psychiatric and medical illnesses, family psychiatric and medical history, demographic info also obtained
Physical exam by orthopedic surgeon and a dysplasia series of radiographs including AP and lateral radiographics of the feet, APs of the knees, pelvis, thoracic lumbar spine and chest, laterals of thoracic lumbar and cervical spine, lateral of the skull, AP and lateral of the forearm, bone age evaluation with radiograph of left hand
exam will determine visual acuity using one of the following: Snellen chart, Allen acuity, target acuity, optokinetic nystagmus (OKN), or Teller acuity depending on study participants ability level. Motility/alignment will also be determined using cover/uncover test. Pupils examined using slit lamp. Dilated fundus exam and cycloplegic refraction which will require dilating drops in both eyes. Cyclogen 1% and NeuSynephrine 2.5% are using. In children less than 6 months old, less potent mydriatrics and cycloplegics are used Cyclogel 0.5% or Tropicamide 1%. Intraocular pressure will be measured in adults and cooperative teens using applanation tonometry. A topical anesthetic will be used to perform this measurement.
physical exam and medical history by board certified gastroenterologist.
University Health Systems Hospital
San Antonio, Texas, United States
RECRUITINGUniversity of Texas Health Science Center at San Antonio
San Antonio, Texas, United States
RECRUITINGPrimary
Provide definitive medical and education resources for the families of individuals with chromosome 18 abnormalities
Time frame: Ongoing
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