Journal of Clinical Medicine (Aug 2019)

<em>APOE</em> Promoter Polymorphism-219T/G is an Effect Modifier of the Influence of <em>APOE</em> ε4 on Alzheimer’s Disease Risk in a Multiracial Sample

  • Kyu Yeong Choi,
  • Jang Jae Lee,
  • Tamil Iniyan Gunasekaran,
  • Sarang Kang,
  • Wooje Lee,
  • Jangho Jeong,
  • Ho Jae Lim,
  • Xiaoling Zhang,
  • Congcong Zhu,
  • So-Yoon Won,
  • Yu Yong Choi,
  • Eun Hyun Seo,
  • Seok Cheol Lee,
  • Jungsoo Gim,
  • Ji Yeon Chung,
  • Ari Chong,
  • Min Soo Byun,
  • Sujin Seo,
  • Pan-Woo Ko,
  • Ji-Won Han,
  • Catriona McLean,
  • John Farrell,
  • Kathryn L. Lunetta,
  • Akinori Miyashita,
  • Norikazu Hara,
  • Sungho Won,
  • Seong-Min Choi,
  • Jung-Min Ha,
  • Jee Hyang Jeong,
  • Ryozo Kuwano,
  • Min Kyung Song,
  • Seong Soo A. An,
  • Young Min Lee,
  • Kyung Won Park,
  • Ho-Won Lee,
  • Seong Hye Choi,
  • Sangmyung Rhee,
  • Woo Keun Song,
  • Jung Sup Lee,
  • Richard Mayeux,
  • Jonathan L. Haines,
  • Margaret A. Pericak-Vance,
  • IL Han Choo,
  • Kwangsik Nho,
  • Ki-Woong Kim,
  • Dong Young Lee,
  • SangYun Kim,
  • Byeong C. Kim,
  • Hoowon Kim,
  • Gyungah R. Jun,
  • Gerard D. Schellenberg,
  • Takeshi Ikeuchi,
  • Lindsay A. Farrer,
  • Kun Ho Lee,
  • Alzheimer’s Disease Neuroimaging Initative

DOI
https://doi.org/10.3390/jcm8081236
Journal volume & issue
Vol. 8, no. 8
p. 1236

Abstract

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Variants in the APOE gene region may explain ethnic differences in the association of Alzheimer’s disease (AD) with ε4. Ethnic differences in allele frequencies for three APOE region SNPs (single nucleotide polymorphisms) were identified and tested for association in 19,398 East Asians (EastA), including Koreans and Japanese, 15,836 European ancestry (EuroA) individuals, and 4985 African Americans, and with brain imaging measures of cortical atrophy in sub-samples of Koreans and EuroAs. Among ε4/ε4 individuals, AD risk increased substantially in a dose-dependent manner with the number of APOE promoter SNP rs405509 T alleles in EastAs (TT: OR (odds ratio) = 27.02, p = 8.80 × 10−94; GT: OR = 15.87, p = 2.62 × 10−9) and EuroAs (TT: OR = 18.13, p = 2.69 × 10−108; GT: OR = 12.63, p = 3.44 × 10−64), and rs405509-T homozygotes had a younger onset and more severe cortical atrophy than those with G-allele. Functional experiments using APOE promoter fragments demonstrated that TT lowered APOE expression in human brain and serum. The modifying effect of rs405509 genotype explained much of the ethnic variability in the AD/ε4 association, and increasing APOE expression might lower AD risk among ε4 homozygotes.

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