Investigating Age-Related Macular Degeneration
|First Received Date ICMJE||June 19, 2006|
|Last Updated Date||April 5, 2012|
|Start Date ICMJE||June 2003|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures ICMJE||Not Provided|
|Original Primary Outcome Measures ICMJE||Not Provided|
|Change History||Complete list of historical versions of study NCT00342251 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures ICMJE||Not Provided|
|Original Secondary Outcome Measures ICMJE||Not Provided|
|Current Other Outcome Measures ICMJE||Not Provided|
|Original Other Outcome Measures ICMJE||Not Provided|
|Brief Title ICMJE||Investigating Age-Related Macular Degeneration|
|Official Title ICMJE||Age-Related Macular Degeneration: A Genetic Epidemiology Study in the Amish|
Age-related macular degeneration (ARMD) affects older Americans and can lead to irreversible blindness. Although the cause if ARMD is unclear, it appears to be a condition that is affected by both genetic and environmental influences.
The purpose of this study is to examine an Amish community to investigate genetic factors in the development of ARMD.
Study participants will be 1,000 members, ages 50 and older, of the Old Order Amish community in Lancaster and Franklin counties in Pennsylvania. Each will undergo a 30-minute dilated eye exam during which an ophthalmologist or optometrist will take digital images of the macula and optic disc. Depending on the results of their eye exam, participants may be asked to give a blood sample as well. They will also complete a brief questionnaire about personal exposure related to occupation, sunlight and smoking.
Age-related macular degeneration (AMD) is a leading cause of visual impairment in the United States. Available evidence suggests that AMD is a complex disorder with a significant genetic component as well as potential environmental influences. In this study we propose to examine 3,000 members, ages 50 and older, of the Old Order Amish community in the Lancaster and Franklin counties area in Pennsylvania. We plan to detail the epidemiology of AMD in this population isolate in attempt to elucidate genetic factors which may confer susceptibility and predispose some Amish individuals and their families to develop AMD. All study participants agreeing to enroll and providing informed consent will undergo a complete, dilated eye examination during which digital stereo images of the macula and optic disc regions will be acquired. Study participants will also be asked to complete a brief questionnaire inquiring about personal exposures related to occupation, sunlight, and smoking. AMD will be determined by an independent reading of the digital fundus photographs by the University of Wisconsin Fundus Photography Reading Center according to the AREDS AMD classification scheme. We will employ standard statistical genetics methods of parametric and non-parametric linkage analysis, association analysis, and transmission disequilibrium tests, with allowances for environmental (i.e. non-genetic) factors to determine if we can identify any candidate regions or candidate genes that predispose Amish individuals to an increased risk of AMD. Ultimately, we hope to follow up any regions that show suggestive evidence of linkage on the genome-wide scan with fine mapping in those regions, leading to eventual cloning and sequencing of a gene or genes.
|Study Type ICMJE||Observational|
|Study Design ICMJE||Time Perspective: Prospective|
|Target Follow-Up Duration||Not Provided|
|Sampling Method||Not Provided|
|Study Population||Not Provided|
|Condition ICMJE||Age-Related Macular Degeneration|
|Intervention ICMJE||Not Provided|
|Study Group/Cohort (s)||Not Provided|
|Publications *||Not Provided|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Recruitment Status ICMJE||Completed|
|Estimated Enrollment ICMJE||3000|
|Completion Date||April 2012|
|Primary Completion Date||Not Provided|
|Eligibility Criteria ICMJE||
All Amish individuals, ages 50 and older, who either respond in the affirmative to the letter of invitation or are self-referred to the Amish clinic for participation in the AMD study, will be eligible.
Individuals who decline participation, who are unwilling to sign the Consent Form, and who are not recognized by the Amish as being Amish will be excluded.
There are no clinical inclusion/exclusion criteria.
|Ages||50 Years and older|
|Accepts Healthy Volunteers||No|
|Contacts ICMJE||Contact information is only displayed when the study is recruiting subjects|
|Location Countries ICMJE||United States|
|NCT Number ICMJE||NCT00342251|
|Other Study ID Numbers ICMJE||999903235, 03-EI-N235|
|Has Data Monitoring Committee||Not Provided|
|Responsible Party||Not Provided|
|Study Sponsor ICMJE||National Eye Institute (NEI)|
|Collaborators ICMJE||Not Provided|
|Information Provided By||National Institutes of Health Clinical Center (CC)|
|Verification Date||April 2012|
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