Education and Training
Natural History Evaluation of Charcot Marie Tooth Disease (CMT) Types CMT1B, CMT2A, CMT4A, CMT4C, and Others
This is an observational longitudinal study to determine the natural history and genotype-phenotype correlations of disease causing mutations in Charcot Marie Tooth disease (CMT) type 1B (CMT1B), 2A (CMT2A), 4A (CMT4A), and 4C (CMT4C).
The investigators will also be determine the capability of the newly developed CMT Pediatric Scale (CMT Peds scale) and the Minimal Dataset to measure impairment and perform longitudinal measurements in patients with multiple forms of CMT over a five year window
Stanford is currently not accepting patients for this trial.
Stanford Investigator(s):
Eligibility
Inclusion Criteria:
All patients must be seen in-person at a participating center for the initial visit.
Inclusion Criteria - patients with CMT (all subtypes)
1. Patient has documented, pathogenic or likely pathogenic CMT-causing variant(s)
OR
2. Patient has a first- or second-degree family member (parent, child, sibling,
half-sibling, aunt, uncle, grandparent, or grandchild) with a documented pathogenic or
likely pathogenic CMT-causing variant AND a clear link between that family member and
the affected patient AND a phenotype consistent with the diagnosis
i. A clear link is necessary for a second-degree relative. For example, if a
grandparent is affected and has a pathogenic or likely pathogenic variant, and the
parent does not have any signs, symptoms, or electrophysiology consistent with the
diagnosis, there is no clear link unless the parent has also been found to have the
pathogenic or likely pathogenic variant such as in cases with reduced penetrance
ii. In cases where clear links are not available, genetic testing is required for the
patient or the family member who is not clearly affected.
3. Patients who have a variant of uncertain significance, as determined by the laboratory
performing the testing may still be included if one of the following circumstances
applies:
i. Variant is categorized as pathogenic or likely pathogenic per the ACMG variant
interpretation guidelines. [80, 81]
ii. Variant has been found in multiple affected people in a family and has not been
found in unaffected family members. (Note - both affected and unaffected family
members must be tested in this situation to be included).
iii. The principal investigator and the site investigator agree that the variant(s) is
(are) most likely pathogenic.
4. Patients whose clinical presentation is suggestive of CMT, but CMT type and variant
are unknown will be characterized by the following categories:
1. Nerve conduction velocities: demyelinating, axonal, intermediate
2. Inheritance: dominant, recessive, X-linked, or unknown
5. Patient or patient's legally authorized representative has understood and signed an
IRB approved consent form for the study. Teenagers (age 13 - 17 years) and cognitively
impaired adults who are able to read and write must sign an assent form (depending on
local ethics committee requirements).
Inclusion Criteria - Controls
1. Person does not have a peripheral neuropathy, as determined by the investigator.
2. Person has understood and signed an IRB approved consent form for the study. Teenagers
(age 13-17 years) must sign an assent form (depending on local ethics committee
requirements).
EXCLUSION CRITERIA
1. Patient has a variant of uncertain significance that cannot be further classified
following methods listed in the Inclusion Criteria.
2. Patient does not wish to be a part of the study or has not signed an informed consent
form.
3. Patient is deemed inappropriate by the Site PI.
Ages Eligible for Study
N/A - N/A
Genders Eligible for Study
All
Not currently accepting new patients for this trial
Contact Information
Stanford University
School of Medicine
300 Pasteur Drive
Stanford,
CA
94305
Carly E Siskind, MS
650-721-5588
Not Recruiting