COVID-19 is an emerging, rapidly evolving situation.
Get the latest public health information from CDC:

Get the latest research information from NIH: Menu

The Genetic Basis of Inherited Neurologic Deficits in People With Schizophrenia

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. Identifier: NCT00247637
Recruitment Status : Completed
First Posted : November 2, 2005
Last Update Posted : July 3, 2013
National Institute of Mental Health (NIMH)
Information provided by (Responsible Party):
Dr. David Braff, University of California, San Diego

Brief Summary:
This is a study of the genetic basis of brain dysfunction in people with schizophrenia.

Condition or disease

Detailed Description:

Schizophrenia is a disabling disorder that is associated with specific inheritable neurobiologic deficits. These deficits can cause problems with memory, visual attention, information processing, and other aspects of daily living. Understanding the genetic components of these deficits in people with schizophrenia and their unaffected family members may help uncover the neurobiological basis, risk factors, and heritability of the disease. In addition, the information may serve to create more effective treatments and possibly a cure for the disease. This study will serve to provide information about the genetic basis of known inherited neurobiological deficits in people with schizophrenia. In turn, this may guide further studies on the genetics of schizophrenia.

Participants will attend 2 study visits, each of which will last approximately 4 hours. The first will include blood tests and diagnostic interviews of participating families to evaluate the presence of schizophrenic symptoms. The second study visit will entail four neurocognitive and neurophysiological tests. Participants will first have a pre-pulse inhibition test, which uses electrodes to measure eye blinking. Electrodes will also be placed on participants' head, ears, and around their eyes to measure brain waves. Next, participants will undergo an oculomotor test, during which they will wear glasses fitted with sensors that record eye movement. Participants will then be asked to repeat a list of words, letters, and numbers read by a researcher. Last, participants will undergo a computerized performance test requiring them to watch the computer screen and click a mouse whenever they see a number between 0 and 9. Each study visit will take approximately 4 hours.

Layout table for study information
Study Type : Observational
Actual Enrollment : 2025 participants
Observational Model: Family-Based
Time Perspective: Cross-Sectional
Official Title: The Genetics of Endophenotypes and Schizophrenia
Study Start Date : May 2003
Actual Primary Completion Date : September 2008
Actual Study Completion Date : September 2008

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Schizophrenia

Primary Outcome Measures :
  1. percent inhibition to the 60 msec prepulse, P50 suppression, proportion of correct saccades, d, number correct in the reorder condition, the total recall score [ Time Frame: Upon entry to the study ]
    The primary outcome measure for each endophenotype is as follows: for prepulse inhibition (PPI) the primary measure is the percent inhibition to the 60 msec prepulse; for P50 suppression it is the difference in amplitude between the test and conditioning stimuli; for antisaccade it is the proportion of correct saccades; for the DS-CPT it is (d') which is based on correct target detections and incorrect responses to nontargets; for LNS it is the number correct in the reorder condition; for CVLT it is the total recall score summed across 5 trials.

Biospecimen Retention:   Samples With DNA
Whole blood was sent to the Cell Repository at Rutgers toestablish cell lines.

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.

Layout table for eligibility information
Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
The subject population will include schizophrenia probands (12 per site per year), first degree relatives (36 per site per year) and normal comparison subjects (15 per site per year). The proband must meet the diagnosis of schizophrenia by DSM-IV criteria. There must be at least one parent and one unaffected sibling in the pedigree. Therefore a total of 315 subjects will be enrolled at each site each year with a total of 2205 enrolled across all 7 sites. Schizophrenia probands and normal subjects will be between 18 and 65 years of age. Exclusion criteria include visual or hearing impairments, history of head trauma, organic brain dysfunction, neurological disease, and significant drug or alcohol use and for controls, significant psychiatric history and/or current use of psychotropic medications. We will include equal numbers of men and women and all appropriate subjects willing to participate regardless of ethnic background.

Inclusion Criteria for Participating Families:

  • Families with at least one member who has schizophrenia

Exclusion Criteria:

  • N/A

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 identifier (NCT number): NCT00247637

Layout table for location information
United States, California
University of California Los Angeles
Los Angeles, California, United States, 90073
University of California, San Diego
San Diego, California, United States, 92103
United States, Colorado
University of Colorado Health Sciences Center
Denver, Colorado, United States, 80220
United States, Massachusetts
Harvard University
Boston, Massachusetts, United States, 02115
United States, New York
Mount Sinai School of Medicine
New York, New York, United States, 10029
United States, Pennsylvania
University of Pennsylvania
Philadelphia, Pennsylvania, United States, 19104
United States, Washington
University of Washington and VA Puget Sound Health Care System
Seattle, Washington, United States, 98108
Sponsors and Collaborators
University of California, San Diego
National Institute of Mental Health (NIMH)
Layout table for investigator information
Study Director: David Braff, MD University of California, San Diego
Layout table for additonal information
Responsible Party: Dr. David Braff, Professor, University of California, San Diego Identifier: NCT00247637    
Other Study ID Numbers: R01MH065571 ( U.S. NIH Grant/Contract )
R01MH065571 ( U.S. NIH Grant/Contract )
R01MH065707 ( U.S. NIH Grant/Contract )
R01MH065578 ( U.S. NIH Grant/Contract )
R01MH065588 ( U.S. NIH Grant/Contract )
R01MH065554 ( U.S. NIH Grant/Contract )
R01MH065562 ( U.S. NIH Grant/Contract )
First Posted: November 2, 2005    Key Record Dates
Last Update Posted: July 3, 2013
Last Verified: July 2013
Keywords provided by Dr. David Braff, University of California, San Diego:
Mental Health
Additional relevant MeSH terms:
Layout table for MeSH terms
Schizophrenia Spectrum and Other Psychotic Disorders
Mental Disorders