The CMT Glossary provides definitions for scientific and medical terms commonly used and heard in CMT.
This resource is offered for general informational purposes only and is not intended to diagnose any medical condition or replace professional medical advice.
Dominant-Negative
aka: dominant negative, dominant-negative effect, antimorph
A mutant protein that disrupts its own normal counterpart, lowering net function.
Dysarthria
aka: slurred speech, speech muscle weakness, difficulty speaking clearly, impaired speech control
Sometimes, CMT can affect the muscles used for speech, and the slurred or effortful result is dysarthria…
Dyspnea
aka: shortness of breath, difficulty breathing, labored breathing, breathlessness, trouble breathing
When CMT reaches the breathing muscles, one result can be dyspnea, the medical word for shortness of breath…
EMG
aka: EMG test, muscle test, nerve and muscle test, muscle electrical test
Alongside the nerve study, people with CMT often get an EMG, a test of the muscles and the nerves that drive them…
F-Wave Latency
aka: F-wave, F response
Among the readings a CMT nerve study captures is F-wave latency, the time a signal takes to travel a nerve all the way to the spinal cord and back…
Fasciculations
aka: muscle twitches, muscle fasciculations
Those small muscle twitches you can feel fluttering under the skin have a name, fasciculations, and they can accompany the nerve changes seen in CMT…
Foot Drop
aka: drop foot, dropped foot
That toe-catching, tripping struggle to lift the front of the foot is foot drop, one of the most recognizable signs of CMT…
Gene
aka: genetic locus, hereditary unit
Every form of CMT begins with a gene: mutations in specific genes are what cause the disease, and because genes pass from parent to child, so can CMT…
Gene Dosage
aka: gene-dosage, copy number, dosage effect
The number of gene copies, and the amount of product they make.
Gene Expression
aka: gene activity, gene turning on and off, how a gene works, gene output, protein production from a gene
Genes carry instructions, and gene expression is how those instructions switch on to build proteins, the process CMT mutations disrupt…
Genetic Heterogeneity
aka: locus heterogeneity, allelic heterogeneity
Why does CMT have so many types, and so many genes behind it? Genetic heterogeneity, many different genes causing one disease, is a big part of the answer…
Haploinsufficiency
aka: haploinsufficient, dosage insufficiency
When one working gene copy is not enough for normal function.
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