How do people get FSHD?

FSHD is caused by a genetic mutation – a fault in the DNA code – which causes a toxic protein to be produced called DUX4. It’s this DUX4 protein which ultimately destroys skeletal muscle cells across the body.

In most cases, FSHD is inherited. FSHD is an autosomal dominant genetic disease, meaning it can be inherited from either parent and is commonly passed down through generations. If a parent has FSHD, each child has a 50% chance of also developing FSHD.

Alternatively, in up to 30% of cases FSHD appears in a family without any previous history of the disease, caused by a spontaneous genetic mutation as a baby is developing in the womb.