In terms of structure, which prion disease displays abnormal aggregation of proteins?

Prion diseases, a group of neurodegenerative disorders, are characterized by the misfolding and abnormal aggregation of proteins known as prion proteins. The unique aspect of prion diseases is that this protein misfolding leads to infectious properties, meaning that the abnormal proteins can induce other normally folded proteins to also misfold.

Kuru, Creutzfeldt-Jakob disease (CJD), and scrapie all exhibit this hallmark feature of abnormal protein aggregation. In Kuru, which was historically observed among certain tribes in Papua New Guinea due to cannibalistic practices, the prion proteins accumulate in the brain tissue, causing severe neurological symptoms. CJD is characterized by rapid cognitive decline and also shows similar protein aggregates in affected brain regions. Scrapie, which affects sheep and goats, leads to signs of neurological dysfunction and is noted for the abnormal clumps of prion proteins in neural tissues.

Since all of these diseases share the common trait of abnormal aggregation of prion proteins leading to their respective pathologies, the assertion that all these prion diseases display this structural alteration is accurate. Thus, the correct answer reflects the foundational understanding of how prion diseases manifest at a molecular level.