Genetic Studies of Inflammatory Bowel Disease

Genetic Study of Inflammatory Bowel Disease

This study will examine the existence of genetic regions that are believed to bring about a risk for inflammatory bowel disease (IBD), with its subtypes of Crohn's disease and ulcerative colitis. It will identify the locations of chromosomes responsible for hereditary IBD through linkage analysis, a technique in genetic research in which the occurrence of a disorder in a family is evaluated alongside a known genetic disorder. The project will also do fine mapping of genes and examine possible genes associated with IBD.

IBD is a chronic and often disabling disorder of the gastrointestinal tract, affecting about 500,000 Americans. Both Crohn's disease and ulcerative colitis share many characteristics, such as abdominal pain, bloody diarrhea, fever, fatigue, and malnutrition. But the main factors that distinguish these subtypes depend on the location and depth of inflammation. Tests and analyses can generally pinpoint some of the differences between the two, but sometimes there are major overlaps in characteristics, and the diagnosis is known as indeterminate IBD. The exact cause of IBD is not known, but genetic and environmental factors are known to contribute to risk for the disease. The single most important environmental risk factor has been smoking exposure at the time the diagnosis is made. Also, several genetic risk factors are ethnicity, family history, and polymorphisms-abilities to take on different forms-in the NOD2 gene.

Patients who have a diagnosis of IBD and their family members 5 years of age and older who have or do not have that diagnosis may be eligible for this study.

Participants will be asked to complete a questionnaire on their health, ethnic background, religion, habits, family medical history, and medications. Information will also be sought on the diagnosis, course, complications, and treatment of IBD, as well as risk factors. In addition, there will be collection of blood to be used for DNA preparation, storage of lymphocytes, and information on immunology.

Study Overview

Status

Completed

Conditions

Detailed Description

Using epidemiological, statistical, and molecular genetic techniques, this proposal is designed to investigate the existence of genetic regions that are believed to confer a risk for inflammatory bowel disease (IBD), which consists of two subtypes, Crohn's disease (CD) and ulcerative colitis (UC). The project will derive its study population, consisting of IBD physician confirmed affected probands with their family members, from the Johns Hopkins University, the University of Chicago, and the University of Pittsburgh. The project will consist of multiple parts. The first part is a reanalysis of existing genome wide linkage data from IBD families with 377 genotyped microsatellite marker data that incorporates covariate data into the analysis, with the goal of identifying new and refining previously identified regions of linkage. Eventually this may be extended to include new families typed for genome wide scan markers. The second part of the project consists of the fine mapping of the IBD3 locus (HLA region on chromosome 6p), which has been shown to have evidence of linkage in UC patients. Fifty-two microsatellite markers spanning the affected child trios in an effort to identify potential marker alleles that may be associated with UC, using the IBD3 locus will be genotyped in a study population consisting of 240 UC father-mother-affected child trios in an effort to identify potential marker alleles that may be associated with UC, using the transmission disequilibrium test, and to identify potential haplotypes that may confer an increased risk of developing UC, using a likelihood-based approach where a moving window of adjacent markers will be tested for excessive transmission. Additional candidate genes within IBD3 will be examined, and polymorphisms will also be tested for potential significant associations. Eventually this second part may be extended to fine mapping and association analysis of other candidate genes and/or candidate regions.

Study Type

Observational

Enrollment

10000

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Illinois
      • Chicago, Illinois, United States, 60637
        • University of Chicago
    • Maryland
      • Baltimore, Maryland, United States, 21205
        • Johns Hopkins Bloomberg School of Public Health
      • Baltimore, Maryland, United States, 21205
        • Johns Hopkins University School Of Medicine
    • Massachusetts
      • Boston, Massachusetts, United States, 02118-2354
        • Boston University Medical Center
    • Pennsylvania
      • Pittsburgh, Pennsylvania, United States, 15261
        • University of Pittsburgh

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child
  • Adult
  • Older Adult

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

  • INCLUSION CRITERIA:

Participants who have a diagnosis of IBD and their family members who have or do not have a diagnosis of IBD will be recruited for this study. Those further selected to be included in the linkage study must have at least two affected family members who are willing to donate blood samples and to fill out medical questionnaires.

EXCLUSION CRITERIA:

Children who were under the age of 5 years were excluded from the Johns Hopkins University recruitment protocol. There was no age restriction for the University of Chicago or the University of Pittsburgh. Those who were not able to provide consent were excluded from the study.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

November 6, 2003

Study Completion

September 19, 2007

Study Registration Dates

First Submitted

June 19, 2006

First Submitted That Met QC Criteria

June 19, 2006

First Posted (Estimate)

June 21, 2006

Study Record Updates

Last Update Posted (Actual)

July 2, 2017

Last Update Submitted That Met QC Criteria

June 30, 2017

Last Verified

September 19, 2007

More Information

Terms related to this study

Other Study ID Numbers

  • 999904045
  • 04-HG-N045

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.