MedlinePlus Genetics
Repeat Expansion - Charcot-Marie-Tooth Disease | Experts in CMT

Repeat Expansion

A short DNA sequence repeated too many times

A repeat expansion is a variant in which a short DNA sequence is repeated many more times than normal. Expanded repeats can cause disease through a toxic gain of function at the RNA or protein level, and they can grow across generations. In CMT, a repeat expansion in NOTCH2NLC underlies a rare subtype.

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