Which of these diseases affects the central nervous system and can be inherited in a familial manner?

• A. Kuru
• B. Scrapie
• C. Gerstmann-Straüssler-Scheinker disease
• D. Normal prion disease

Answer: (C)

Gerstmann-Straüssler-Scheinker disease is a neurodegenerative disorder that is classified among the transmissible spongiform encephalopathies (TSEs). This disease is known to have a strong genetic component, being inherited in an autosomal dominant manner. It is caused by mutations in the PRNP gene, which encodes the prion protein, leading to the accumulation of misfolded proteins in the brain and resulting in severe neurological damage.

Familial cases of Gerstmann-Straüssler-Scheinker disease often present with symptoms such as ataxia, dementia, and other cognitive impairments, typically appearing in mid to late adulthood. The hereditary nature of this disease contrasts with others mentioned in the options, which do not have a clear familial inheritance pattern or are primarily associated with non-genetic transmission.

In contrast, Kuru and scrapie, while they are prion diseases, are not typically inherited in a familial manner. Kuru is historically associated with cannibalistic practices among certain New Guinean tribes, and scrapie primarily affects sheep and goats without a genetic basis for human inheritance that aligns with Gerstmann-Straüssler-Scheinker disease. Normal prion disease is not well-defined as