We are updating the design of this site. Learn more.
Show more
ClinicalTrials.gov
ClinicalTrials.gov Menu

Studies of Families With Hereditary Cataracts

This study has been completed.
Sponsor:
ClinicalTrials.gov Identifier:
NCT00001609
First Posted: November 4, 1999
Last Update Posted: March 4, 2008
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Information provided by:
National Institutes of Health Clinical Center (CC)
  Purpose

The objective of this study is to discover the genes responsible for the development of hereditary cataracts in families. A cataract is clouding of the lens of the eye that obstructs the passage of light and may impair vision. Information from this study may provide a better understanding of why hereditary cataracts form and perhaps lead to the development of a test that can predict who will likely be affected and to what degree.

Patients or family members of patients with inherited cataracts who participate in this study will be asked questions about their family history, especially concerning eye disease or cataracts, and a family tree will be drawn. They will undergo a complete eye examination, including photographs to document the clarity or opacity of the lens. In addition, a small blood sample will be drawn for use in gene mapping studies of inherited cataract.


Condition
Cataract Congenital Anomaly

Study Type: Observational
Official Title: Clinical and Molecular Studies in Families With Congenital or Hereditary Cataracts

Resource links provided by NLM:


Further study details as provided by National Institutes of Health Clinical Center (CC):

Estimated Enrollment: 1200
Study Start Date: October 1996
Estimated Study Completion Date: March 2003
Detailed Description:
Although the etiology of some secondary cataracts is becoming better understood and certain animal models have the promise to elucidate the relationships between lens crystallin and hereditary cataract, little is known about the causes of congenital cataracts in humans. Even the classification of different types of cataracts is cumbersome and imperfect. A better understanding of cataractogenesis will come through an understanding of the molecular components of the lens of the eye and the ways in which lesions of these components are manifested structurally and functionally as opacity of the lens. It is well known that cataracts exhibit marked genetic heterogeneity. In mice and humans, hereditary cataracts have been shown to result from lesions at many distinct loci and those cataracts corresponding to one locus can be morphologically heterogeneous, implying that environmental factors may modify the phenotype of the cataract which a molecular lesion causes. Nonetheless, molecular biological characterization of cataracts in the mouse and guinea pig has suggested that alterations in lens crystallins can cause hereditary cataracts making them reasonable candidate genes for causing hereditary cataracts in humans. In addition, it is apparent that hereditary lesions which mimic or contribute additively to environmental stresses known to cause cataracts might be candidate genes for causing hereditary cataracts. This knowledge increases the feasibility of genetic linkage studies and provides a rationale basis on which to begin the molecular analysis of naturally occurring hereditary cataracts. Therefore, it is the purpose of this protocol to concentrate upon hereditary cataracts.
  Eligibility

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.


Ages Eligible for Study:   Child, Adult, Senior
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Criteria

The proband must have documentation of congenital or hereditary cataract.

Patients with cataract due to radiation, steroid, or associated with other ocular diseases such as uveitis, retinitis pigmentosa etc. and age-related cataracts will be excluded.

  Contacts and Locations
Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00001609


Locations
United States, Maryland
National Eye Institute (NEI)
Bethesda, Maryland, United States, 20892
Sponsors and Collaborators
National Eye Institute (NEI)
  More Information

Publications:
ClinicalTrials.gov Identifier: NCT00001609     History of Changes
Other Study ID Numbers: 970009
97-EI-0009
First Submitted: November 3, 1999
First Posted: November 4, 1999
Last Update Posted: March 4, 2008
Last Verified: March 2003

Keywords provided by National Institutes of Health Clinical Center (CC):
Linkage
Genetic Analysis
Lens
Opacity
Inherited
Linkage Analysis
Genomic DNA
Risk Prediction
Pedigree Analysis
Congenital Cataracts
Hereditary Cataracts

Additional relevant MeSH terms:
Cataract
Congenital Abnormalities
Lens Diseases
Eye Diseases