APOE ε4 is considered a marker for poor prognosis in various diseases, but APOE ε2 rather than APOE ε4 has been associated with cerebral amyloid angiopathy-related bleeding and sporadic Parkinson's disease.
In contrast to reports in oriental populations, our results do not support a major role of APOE, PARKIN and COMT polymorphisms in PD susceptibility in the Finnish population.
A recent study showed significant association of sporadic Parkinson's disease with a polymorphism within the alpha-synuclein gene and closely linked DNA markers on chromosome 4q and the APOE epsilon4 allele.
The frequency of the APOE allele epsilon4 was similar in patients with Parkinson's disease and controls, but the APOE allele epsilon2, thought to be protective for dementia, was significantly more frequent in patients with sporadic Parkinson's disease than in controls.