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.
Haploinsufficiency
aka: haploinsufficient, dosage insufficiency
When one working gene copy is not enough for normal function.
Heterozygote
aka: heterozygous
In CMT, a dominant subtype comes down to being a heterozygote: one normal copy of the gene, and one copy carrying the mutation that causes the disease…
Heterozygous
aka: heterozygote, heterozygosity
In CMT, a dominant subtype is heterozygous: only one copy of the mutated gene, from one parent, is enough to cause the disease…
Homozygote
aka: homozygous
The recessive forms of CMT require a homozygote, someone who inherited the very same mutated gene copy from both parents…
Homozygous
aka: homozygote, homozygosity
The recessive forms of CMT are homozygous: two copies of the same mutated gene, one from each parent, are needed to cause the disease…
Hypomorphic Allele
aka: hypomorph, hypomorphic variant, partial loss-of-function allele
A variant that partially reduces, but does not abolish, normal function.
Hypotonia
aka: low muscle tone, floppiness
Some children with CMT are described as floppy or low-toned, and that soft, reduced muscle tension has a name: hypotonia…
Interchromosomal / Insertion Translocation
aka: interchromosomal insertion, insertion translocation, insertional translocation, structural variant
A chromosome segment inserted into a different chromosome; the cause of CMTX3.
Intermediate CMT
aka: intermediate neuropathy, dominant intermediate CMT
Some CMT does not fit neatly into demyelinating or axonal, its nerve signals fall in between, and that in-between form is intermediate CMT…
Intermediate Neuropathy
Some CMT sits between the two main types by nerve conduction, neither clearly demyelinating nor axonal, and that is intermediate neuropathy…
KAFO
aka: Knee Ankle Foot Orthosis, long leg brace
When CMT weakness reaches the knee as well as the foot and ankle, the KAFO is the brace that steps up to support all three…
Loss of Function
aka: LoF, loss-of-function
A variant that reduces or removes a protein's normal activity.
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