Multi-Center African-American Inflammatory Bowel Disease Study (MAAIS): The Search for New Genes
Recruitment status was Recruiting
|First Received Date ICMJE||June 16, 2010|
|Last Updated Date||July 6, 2011|
|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 NCT01169194 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||Multi-Center African-American Inflammatory Bowel Disease Study (MAAIS): The Search for New Genes|
|Official Title ICMJE||Multi-Center African-American Inflammatory Bowel Disease Study (MAAIS)|
The investigators are doing the research to discover genes that cause Inflammatory Bowel Disease (IBD) specifically in the African American population. Who May Join This Study? Blacks / African Americans with or without Crohn's disease or ulcerative colitis.
If you agree to join the study, the investigators ask that you give us information about your health. The investigators will also ask you to give us a blood sample so that they may discover the genes that cause IBD. The blood sample may be collected at Johns Hopkins or any local facility convenient to you.
This current protocol was established as part of an NIDDK consortium initiative to further explore genetic factors associated with IBD. Specifically, the investigators are interested in identifying the genetic, environment and socio-economical components that contribute to the development of IBD in the African American population.
Positional identification of IBD genes has only been performed in ancestral European American (EA) populations. Recent reports have found that IBD incidence may be similar in both AA and EA (Kurata et al. 1992). Because of different ancestry, AA IBD risk alleles may be unique. For example, the investigators did not find any of the common NOD2 mutations in an initial genotyping of a small set of the AA CD patients. A search of the scientific literature demonstrates that of the greater than 1000 published studies concerning IBD gene mapping, gene association or simply genetic epidemiology, none contained reference to IBD in "blacks or African Americans." Therefore, the genetics of IBD in African Americans is unknown. The goal of the study is to understand the genetics of IBD in African Americans. The investigators will specifically characterize the IBD1, IBD3, and IBD5 genetic loci in these populations. In addition, the investigators will investigate the possible role of variations in the OCTN cation transporter genes which were recently found to be associated with Crohn's disease in a European population.
IBD is believed to be caused by a combination of environmental and genetic factors. Genotype data will be examined alongside potential environmental factors such as smoking, medications, environmental exposures, and some dietary factors. Since IBD is known to predominantly affect Western, industrialized areas of the world, the investigators will also inquire about participants' socioeconomic background in hopes of identifying any previously unknown factors in the AA population that may increase the risk of IBD in this population. These potential environmental factors will be important in association analyses using covariates as these factors can obscure potential associations or interact with genetic factors and thus contribute to genetic associations. The investigators will also obtain information as to ancestry of parents and grandparents as to best match cases with unrelated controls of similar ancestry (e.g., Caribbean, recent European or recent African ancestry could cause genetic mismatch of a case and control). At the same time, the investigators will also collect similar information (smoking, medications, environmental exposures and dietary factors) from non-African Americans for the purpose of making direct comparisons for these parameters between the different racial groups to assess the contribution of non-genetic factors for susceptibility to the development of IBD.
The protocol calls for recruiting AA patients and ethnically matched controls (friend or spouse) and relatives with or without IBD. These persons will provide us with a blood sample and with information requested on a questionnaire asking the following: clinical course and history of their IBD or their general health, smoking history, socioeconomic variables and specific dietary factors known in some populations to be related to IBD etiology. Access to medical records will be used to confirm diagnoses. The clinical characteristics of IBD obtained from medical records will be summarized in a phenotyping form using a standardized NIDDK IBDGC Phenotyping Operations Manual. Controls will be asked health history to identify potentially unrecognized IBD. Parents and siblings can be used as within-family controls (particularly for family based linkage disequilibrium testing), more distant relatives can be useful for determining haplotypes and, when a family history of IBD is present, for potential linkage analysis testing for chromosomal regions shared in affected relative pairs. Such analyses are very robust to unrecognized population stratification; no such studies have been performed in the AA population. DNA will be purified from blood and used to identify genetic polymorphisms associated with AA IBD, as compared to within-family and unrelated controls. Samples and data will also be shared with the NIDDK IBD GC for use in IBDGC research projects. They will be processed and stored by the Rutgers University/Cell Repository and the NIDDK IBDGC Data Coordinating Center at University of Chicago. In addition, serum samples purified from blood will be processed and stored at Fisher Bioservices for Consortium projects.
Recruitment will also target non-African American patients for comparison purposes. These patients will be administered the same questionnaire. At the time of enrollment, no blood draw is required but permission is requested from the participant to be contacted at a future date should a blood draw be needed. Participants are not obligated to provide a blood sample at a later time and will only do so after signing a new consent giving us explicit permission.
A secondary goal of this study is to determine whether there are racial differences in the IBD health outcomes and health utilization. The investigators will be comparing African Americans subjects to the white comparison group detailed above. In addition to the clinical questionnaire above, a phone interviewer will contact a subset of the IBD patients (adults ages 18 and older) to ask if they are willing to participate in a phone survey and to obtain verbal consent. This health services supplemental questionnaire will inquire about insurance access, physician utilization, health-related quality of life, indices of disease severity, income, occupational history, patient-reported adherence, and patient trust-in-physicians.
|Study Type ICMJE||Observational|
|Study Design ICMJE||Observational Model: Case Control
Time Perspective: Cross-Sectional
|Target Follow-Up Duration||Not Provided|
|Biospecimen||Retention: Samples With DNA
Blood samples from each participant will be sent to the NIDDK repository for DNA purification, sample distribution, establishment of cell lines. Serum samples will be sent to Fisher Bioservices Repository.
All additional samples will be processed and stored at Dr. Brant's Johns Hopkins IBD Genetics Laboratory with isolated lymphocytes and cell cultures made and stored at the Johns Hopkins Cell Center with use restricted to the PI (Dr. Brant).
|Sampling Method||Non-Probability Sample|
Patient's of gastroenterology departments at medical centers.
|Condition ICMJE||Inflammatory Bowel Disease|
|Intervention ICMJE||Not Provided|
|Study Group/Cohort (s)||
|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||Recruiting|
|Estimated Enrollment ICMJE||2400|
|Completion Date||Not Provided|
|Primary Completion Date||Not Provided|
|Eligibility Criteria ICMJE||
|Ages||5 Years and older|
|Accepts Healthy Volunteers||Yes|
|Listed Location Countries ICMJE||United States|
|Removed Location Countries|
|NCT Number ICMJE||NCT01169194|
|Other Study ID Numbers ICMJE||03-09-11-09, 1 UO1 DK62431|
|Has Data Monitoring Committee||Yes|
|Responsible Party||Steven R. Brant, M.D., Johns Hopkins University-School of Medicine|
|Study Sponsor ICMJE||Johns Hopkins University|
|Information Provided By||Johns Hopkins University|
|Verification Date||July 2011|
ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP