<i>APOE</i> Alleles With Tau and Aβ Pathology in Patients With Amyotrophic Lateral Sclerosis and Parkinsonism-Dementia Complex in the Kii Peninsula.

Abstract

To examine the association of the <i>APOE</i> 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). We analyzed <i>APOE</i> 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 <i>APOE</i> variants and Aβ and tau pathologies. The frequency of the ε4 allele was not different between patients with Kii ALS/PDC and control participants. <i>APOE</i> ε4 was associated with increased Aβ pathology (<i>p</i> = 0.005 by the <i>χ</i> ² test), but not with increased tau pathology (<i>p</i> = 0.984). The frequency of the ε2 allele was apparently higher than that of control participants (<i>p</i> = 0.254). The <i>APOE</i> ε2 allele was associated with increased tau pathology (<i>p</i> = 0.009) and not with reduced Aβ pathology (<i>p</i> = 0.383) in patients with Kii ALS/PDC. 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.