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Genetics and inheritance

C9orf72

The most common genetic cause of ALS/MND, and also of frontotemporal changes.

What it means

A short piece of genetic code that is normally repeated a small number of times is repeated far more often. It is the inherited cause found most often in ALS/MND, and the same change can cause frontotemporal changes, which is why the two are often discussed together.

Why you might hear it

  • It is usually included in genetic testing panels.
  • It explains why some families see both movement and thinking changes.

People who may help

Where Compass goes into this

About this explanation

These are plain explanations of words you may come across, not advice about your own situation. Where a word matters to a decision, the question pages go into it properly, and your own team is the place to take it.