Inherited CJD is a very rare genetic condition where one of the genes a person inherits from their parent (the prion protein gene) carries a mutation that causes prions to form in their brain during adulthood, causing the symptoms of CJD.

 

The symptoms of inherited CJD usually first develop in people in their early 50s.

 

Inherited CJD affects around 1 in every 9 million people in the UK and caused 8 deaths in the UK in 2017 (along with similar inherited prion diseases).