Ishii K, Sakata M, Oda K, Toyohara J, Ishiwata K, Senda M, Ito K, Kuwano R, Iwatsubo T.
Influence of APOE genotype on amyloid deposition in Japanese population. Direct comparison of J-ADNI, USADNI and AIBL 11C-PiB PET data.
Human Amyloid Imaging 2011 Meeting Abstracts. 2011 Jan 15;
It has not been established whether the association between Alzheimer's disease (AD), apolipoprotein E (APOE) ε4
allele, and amyloid deposition is similar in different between ethnic groups. In this study, we evaluated the influence
of APOE ε4 on the cortical accumulation of 11C-Pittsburgh compound B (PiB) in three multi-center imaging studies
of Alzheimer's disease; Alzheimer's Disease Neuroimaging Initiative (US-ADNI), Australian Imaging Biomarker and
Lifestyle Flagship Study of Aging (AIBL), and Japanese Alzheimer's Disease Neuroimaging Initiative (J-ADNI).
We analyzed the initial 11C-PiB scan data from US-ADNI: 19 cognitively normals (NL) (78.3} 5.3 year old, mean} SD), 64 mild cognitive impairment (MCI) subjects (75.5} 7.9), and 19 AD patients (73.4} 8.7), AIBL: 119 NL
(73.1} 7.3), 41 MCI (76.0} 7.2), 27 AD (73.1} 8.8), and J-ADNI: 46 NL (66.3} 4.6), 32 MCI (69.4} 12.2), and
21 AD (74.3} 6.0). The 11C-PiB PET images were acquired 50-70 min post-injection in US-, and J-ADNI, whereas
40-70 min in AIBL. The PET images were coregistered to individual MRI data, and mean cortical standardized
uptake value ratio (mcSUVR) in reference to cerebellar cortex was measured with the same platform of data
analysis using DARTEL template, standard set of regions of interest, and cerebrospinal fluid volume correction.
The cut-off mcSUVR value for PiB-positivity was set at 1.5 for all the studies.
The PiB-positive rate (%) in each group with or without ε4 allele (ε4+/ε4-) were; NL (80/57), MCI (83/52), AD
(100/88) in US-ADNI; NL (56/23), MCI (88/31), AD (100/100) in AIBL; and NL (59/7), MCI (100/44), AD (100/80)
in J-ADNI. The averaged mcSUVR of PiB-positive subjects in each group by the number of ε4 allele (0, 1, 2)
were; NL (1.9, 2.1, -), MCI (2.2, 2.3, 2.6), AD (2.2, 2.2, 2.6) in US-ADNI; NL (1.9, 2.1, 2.3), MCI (1.9, 2.3, 2.5), AD
(2.4, 2.4, 2.5) in AIBL; and NL (1.8, 2.0, 2.1), MCI (2.1, 2.3, 2.4), AD (2.2, 2.3, 2.3) in J-ADNI. Positive influence of
APOE ε4 allele on amyloid deposition with gene dose effect was observed in Japanese population similarly as
observed in US-ADNI and AIBL studies.
We conclude that the effect of APOE ε4 allele on amyloid deposition is similar in Japanese population to those in
caucasians, despite the lower ε4 allele frequency in the Japanese population.