Familial forms of prion disease are typically inherited in an autosomal dominant manner. This means that only one copy of the mutated gene, inherited from either parent, is sufficient to cause the disease. Prion diseases are associated with mutations in the PRNP gene, which encodes the prion protein (PrP). When this gene undergoes certain mutations, it can lead to the production of an abnormal, misfolded form of the prion protein, which can then induce other normal prion proteins to also misfold, leading to the progression of the disease.

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