Background and objectives: To examine the association of the APOE ε4 and ε2 alleles with the pathologic features of patients with amyotrophic lateral sclerosis and parkinsonism-dementia complex cases in the Kii peninsula of Japan (Kii ALS/PDC).
Methods: We analyzed APOE variants in 18 autopsy patients with ALS/PDC, consisting of 9, 8, and 1 patient with PDC, ALS, and PDC followed by ALS, respectively. Moreover, we revealed the relationship between APOE variants and Aβ and tau pathologies.
Results: The frequency of the ε4 allele was not different between patients with Kii ALS/PDC and control participants. APOE ε4 was associated with increased Aβ pathology (p = 0.005 by the χ 2 test), but not with increased tau pathology (p = 0.984). The frequency of the ε2 allele was apparently higher than that of control participants (p = 0.254). The APOE ε2 allele was associated with increased tau pathology (p = 0.009) and not with reduced Aβ pathology (p = 0.383) in patients with Kii ALS/PDC.
Discussion: Although there was no overrepresentation of the frequency of the ε4 or ε2 allele, our findings suggest that the ε2 allele is associated with increased tau pathology and not with reduced Aβ pathology in patients with Kii ALS/PDC.
© 2022 American Academy of Neurology.