Genetic association of a cathepsin D polymorphism and sporadic creutzfeldt-jakob disease

Background: Cathepsin D is the most abundant lysosomal and endosomal aspartyl protease; it shows beta and gamma secretase activity in vitro by cleaving the amyloid precursor protein into amyloid beta protein. In recent studies, cathepsin D was co-localized with PrP^Sc, the disease-associated form of the prion disease, and abnormal expression of cathepsin D correlated with tissue damage in brains of sporadic Creutzfeldt-Jakob disease (CJD). Objective: To investigate whether a polymorphism at position 224, C224T, on exon 2 of the cathepsin D gene (CTSD) is associated with sporadic CJD in the Korean population. Methods: We compared the genotype and allele frequencies at this polymorphism site in 172 sporadic CJD patients with those in 197 healthy Koreans. Results and Conclusion: Our study does not show a significant difference in genotype (p = 0.901) and allele (p = 0.509) frequencies of CTSD C224T between sporadic CJD patients and normal controls. This was the first genetic association study of CTSD in a sporadic CJD population.