NCT01193088 · University of Iowa
Genetics of Charcot Marie Tooth (CMT) - Modifiers of CMT1A, New Causes of CMT2
(INC-6602)
What this study is about
This project includes two projects. One is looking for new genes that cause Charcot Marie Tooth disease (CMT). The other is looking for genes that do not cause CMT, but may modify the symptoms a person has.
View original scientific description
This project includes two projects. One is looking for new genes that cause Charcot Marie Tooth disease (CMT). The other is looking for genes that do not cause CMT, but may modify the symptoms a person has.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- All patients must agree to take part in the study and sign a consent form. A teenager (age 13-17 years) considering enrolling must agree to take part in the study and sign an assent form (depending on local ethics committee requirements). Additional inclusion criteria are described below. Inclusion Criteria: CMT1A Gene Modifier Study Patients must have at least one of the following:
- Patient has a documented PMP22 duplication. AND/OR
- Patient has a first or second degree relative (parent, child, sibling, half- sibling, aunt, uncle, grandparent, grandchild, niece, or nephew) with a documented PMP22 duplication AND a clear link between that family member and the affected patient AND a phenotype consistent with CMT1A. i. A clear link is necessary for a second-degree relative. For example, if a grandparent is affected and has a PMP22 duplication, and the parent does not have any signs, symptoms, or electrophysiology consistent with CMT1A, there is no clear link. ii. In cases where clear links are not available, genetic testing is required for the patient or the first degree family member who is not clearly affected. Inclusion Criteria - Patients for CMT Exome Project a. Patient has demonstrated neuropathy on nerve conduction studies or clinically diagnosed genetic neuropathy, in the opinion of the investigator or genetic counsellor. Inclusion Criteria - Controls for CMT Exome Project
- Person is a family member of a CMT patient who is enrolled in the CMT Exome Project. AND one of the following:
- Person does not have a peripheral neuropathy, in the opinion of the investigator or genetic counsellor. OR
- Person is suspected to have a peripheral neuropathy, but has not been examined at an INC site.
Exclusion criteria
- Patient does not wish to participate or does not sign a consent form.
- For CMT Exome Project, patient has a genetically confirmed form of CMT (i.e. mutation in MFN2 causing CMT2A, mutation in GARS causing CMT2D, etc.).
- Patients with known neuropathy from a non-genetic source, such as chemotherapies (i.e. Vincristine, Taxol, Cisplatin), diabetes, alcoholism will be evaluated independently so that genetic contributions to their effects on CMT1A phenotypes can also be analyzed.
Where
- Los Angeles, California
- Palo Alto, California
- Aurora, Colorado
- Hartford, Connecticut
- Miami, Florida
- Iowa City, Iowa
- Baltimore, Maryland
- Boston, Massachusetts
- Ann Arbor, Michigan
- Maple Grove, Minnesota
- Rochester, New York
- Chapel Hill, North Carolina
And 4 more locations — see the full list below.
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Oct 7, 2025 · Source of record for eligibility and locations