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.
Pathogenic
aka: disease-causing, pathogenic variant
When a CMT genetic test calls a variant pathogenic, it is saying the evidence points to this change causing the disease…
Pathogenic Variant
aka: pathogenic mutation, disease-causing variant, mutation
A DNA change that causes or contributes to disease.
Pelvic Girdle
aka: hip girdle, pelvis
As CMT weakness climbs from the feet, it can reach the pelvic girdle, the ring of bone that links the spine to the legs…
Penetrance
aka: complete penetrance, reduced penetrance
Why can the same CMT variant affect two people in the same family so differently? Penetrance is part of the answer…
Peripheral Nervous System
aka: PNS
CMT is a disease of the peripheral nervous system, the vast web of nerves that connect the brain and spinal cord to the rest of…
Peroneal Muscle
aka: fibularis muscles, peroneals
The peroneal muscles are the muscles on the outer lower leg that help steady the foot and ankle, and they are among…
Peroneal Nerve
aka: fibular nerve, common peroneal nerve
The peroneal nerve, which lifts the foot, is almost always affected in CMT, which is why foot drop is so common…
Pes Cavus
aka: high arch, high-arched foot
The high-arched foot is so common in CMT that it is often called a hallmark of the disease, its formal name is pes cavus…
Pes Planus
aka: flat foot, flatfoot, fallen arches
Not every CMT foot has a high arch, sometimes it is the opposite, a flat foot known as pes planus…
Phrenic Nerve
aka: diaphragmatic nerve
When CMT impacts the breathing muscles, the phrenic nerve is part of the why…
Polyneuropathy
aka: peripheral polyneuropathy
CMT affects many nerves at the same time, which makes it a polyneuropathy: poly meaning many…
Proband
aka: index case, propositus
In a family with CMT, the proband is the first person diagnosed, the one whose case brings the whole family's history to light…
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