For example, although 219E/K heterozygosity confers resistance against the development of sporadic CJD, this genotype is not entirely protective against acquired forms (iatrogenic CJD and variant CJD) or genetic forms (genetic CJD and Gerstmann-Sträussler-Scheinker syndrome) of prion diseases.
Prion protein gene (PRNP) E219K is a human polymorphism commonly occurring in Asian populations but is rarely found in patients with sporadic Creutzfeldt-Jakob disease (CJD).
In addition, we examined 43 patients with dementia of non-CJD origin, and 4 were found to have the codon 219Glu/Lys heterozygous polymorphism with a similar allele frequency as in the general population.