PRNP Val129 homozygosity increases risk for early-onset Alzheimer's disease

We analyzed the PRNP M129V polymorphism in a Dutch population‐based early‐onset Alzheimer's disease sample. We observed a significant association between early‐onset Alzheimer's disease and homozygosity of M129V (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.1–3.3; p = 0.02) with the highest risk for V homozygotes (OR, 3.2; 95% CI, 1.4–7.1; p < 0.01). In patients with a positive family history, these risks increased to 2.6 (95% CI, 1.3–5.3; p < 0.01) and 3.5 (95% CI, 1.3–9.3; p = 0.01), respectively. Ann Neurol 2003;53;409–412