APOE in non-Alzheimer amyloidoses: transmissible spongiform encephalopathies.

BACKGROUND

The APOE genotype has been shown to influence the risk of developing sporadic and familial AD. This effect is isoform-dependent, the APOE epsilon4 allele increasing susceptibility and the APOE epsilon2 allele providing protection. Amyloid formation is an important part of the pathogenesis in AD as well as in spongiform encephalopathies; apoE deposition in amyloid plaques has been documented in both conditions.

METHODS

We examined the frequency of the APOE alleles in patients with various forms of transmissible spongiform encephalopathies, or prion diseases, including sporadic and iatrogenic Creutzfeldt-Jakob disease; familial Creutzfeldt-Jakob disease associated with PRNP 178N/129V and 200K/129M point mutations and a 24-nucleotide repeat expansion; fatal familial insomnia caused by the 178N/129M mutation; Gerstmann-Sträussler-Scheinker disease associated with 102L/129M mutation; and kuru.

RESULTS

None of the groups we studied had a significant excess of APOE epsilon4 allele when compared with appropriate controls.

CONCLUSION

Our results do not support the contention that the APOE epsilon4 allele is a risk factor for developing Creutzfeldt-Jakob disease or related disorders.