Molecular Genetics of Retinal Degenerations

NCT00231010 | Completed

• 2 other identifiers: 05014305-EI-0143
• Study Type: observational
• Target: 3,549
• Locations: 4 countries
• Sites: 6

Brief Summary

This multinational study will investigate the inheritance of genetic retinal degeneration in families of different nationalities and ethnic backgrounds in order to identify the genes that, when altered, cause retinal degeneration. The retina is a light-sensitive membrane lining the back part of the eye. It relays vision signals to the brain, which the brain interprets into sight. When the retina degenerates, vision is altered and possibly lost. The findings of this study should help improve diagnosis and methods of treatment for these disorders. Participating institutions include: the National Institutes for Health in Bethesda, Maryland; the University of Miami in Florida; the Casey Eye Institute in Portland, Oregon; the Byrd Health Sciences Center in Morgantown, West Virginia; the University of Texas Southwestern Medical School in Dallas, Texas; the University of Tennessee Health Sciences Center in Memphis; the Prasad Eye Institute in Hyderabad, India; National Center of Excellence in Molecular Biology in Lahore, Pakistan; and the Jules Gonin Hospital in Lausanne, Switzerland. Patients with retinitis pigmentosa and closely related diseases such as Usher syndrome, snowflake vitreoretinal dystrophy and Bietti crystalline dystrophy may be eligible for this study. Participants undergo the following tests and procedures:

• Medical and surgical history, including family history of vision problems.
• Examination to clarify the type of retinal degeneration.
• Eye examination, including tests of color vision, field of vision and ability to see in the dark
• Electroretinogram to test the function of visual cells. For this test, the patient sits in a dark room for 30 minutes with his or her eyes patched. Then, a small electrode (silver disk) is taped to the forehead and the eye patches are removed. The surface the eyes is numbed with eye drops, and contact lenses are placed on the eyes. The patient looks inside a large dark globe that emits a series of light flashes. Then a light is turned on inside the globe and more lights flash. The contact lenses sense small electrical signals generated by the retina when the light flashes.
• Hearing tests for patients with a personal or family history of deafness. Tests include an audiogram, ear examination and test of middle ear function. For middle ear function testing, the patient feels a little air pressure change for a moment and hears some tones. Another test requires the patient to sit quietly with electrodes on the head, forehead and earlobes.
• Balance testing, including walking in a straight line, standing with eyes closed in the dark and other tests of coordination, and caloric testing. For the caloric testing, any ear wax in the ear canal is removed before the test begins. Then, electrodes are placed on the skin near the eyes and on the forehead. A small amount of cool (sometimes cold) or warm water is instilled into each ear canal, first one and then the other.
• Blood sample collection for genetic testing.

Conditions

Retinal Degeneration; Retinitis Pigmentosa

Keywords

Retnitis Pigmentosa; Retinal Degeneration; Retinitis Pigmentosa; RP; Usher Syndrome; USH; Bietti Crystalline Dystrophy; BCD

Outcome Measures

Primary Outcomes (1)

• V

  Ongoing

Eligibility Criteria

• Age: 4 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients that meet diagnostic criteria for specific retinal degenerations will be recruited from the NEI and collaborating clinics.
• Subjects with the following will be recruited:
• Individuals or family members of individuals with Retinal degenerations, either congenital, childhood, or age related.
• Adults must be capable of providing their own consent.
• All subjects must be able to cooperate with study examination and phlebotomy.
• Older than 4 years of age.

You may not qualify if:

• Diseases, infections, or trauma that mimic primary retinal degenerations.
• Children requiring sedation for study procedures.

Sponsors & Collaborators

• National Eye Institute (NEI): lead

Study Sites (6)

National Institutes of Health Clinical Center, 9000 Rockville Pike

Bethesda, Maryland, 20892, United States

Location

Harvard Medical School

Boston, Massachusetts, 02115, United States

Location

Cleveland Clinic Foundation Childrens Hospital

Cleveland, Ohio, 44195, United States

Location

Sun Yat-Sen University

Guangzhou, 510275, China

Location

Aravind Eye Hospital

Maduri, India

Location

University of Punjab

Lahore, Pakistan

Location

Related Publications (3)

• Smith RJ, Pelias MZ, Daiger SP, Keats B, Kimberling W, Hejtmancik JF. Clinical variability and genetic heterogeneity within the Acadian Usher population. Am J Med Genet. 1992 Aug 1;43(6):964-9. doi: 10.1002/ajmg.1320430612.

  PMID: 1415347 BACKGROUND

• Keats BJ, Todorov AA, Atwood LD, Pelias MZ, Hejtmancik JF, Kimberling WJ, Leppert M, Lewis RA, Smith RJ. Linkage studies of Usher syndrome type 1: exclusion results from the Usher syndrome consortium. Genomics. 1992 Nov;14(3):707-14. doi: 10.1016/s0888-7543(05)80172-7.

  PMID: 1427898 BACKGROUND

• Smith RJ, Lee EC, Kimberling WJ, Daiger SP, Pelias MZ, Keats BJ, Jay M, Bird A, Reardon W, Guest M, et al. Localization of two genes for Usher syndrome type I to chromosome 11. Genomics. 1992 Dec;14(4):995-1002. doi: 10.1016/s0888-7543(05)80122-3.

  PMID: 1478678 BACKGROUND

MeSH Terms

Conditions

Retinal Degeneration; Retinitis Pigmentosa; Usher Syndromes; Bietti Crystalline Dystrophy

Condition Hierarchy (Ancestors)

Eye Diseases, Hereditary; Eye Diseases; Retinal Diseases; Retinal Dystrophies; Genetic Diseases, Inborn; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Deaf-Blind Disorders; Deafness; Hearing Loss; Hearing Disorders; Ear Diseases; Otorhinolaryngologic Diseases; Hearing Loss, Sensorineural; Sensation Disorders; Neurologic Manifestations; Nervous System Diseases; Blindness; Vision Disorders; Abnormalities, Multiple; Congenital Abnormalities; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• James F Hejtmancik, M.D.

  National Eye Institute (NEI)

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: FAMILY BASED
• Time Perspective: OTHER
• Sponsor Type: NIH
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 30, 2005
• First Posted: October 3, 2005
• Study Start: September 26, 2005
• Study Completion: June 23, 2016
• Last Updated: April 5, 2018

Record last verified: 2016-06-23

Locations

IN (1); CN (1); US (3); PA (1)