Neurological Sciences

, Volume 32, Issue 4, pp 559–569 | Cite as

The concept of FDG-PET endophenotype in Alzheimer’s disease

  • Emmanuel H. During
  • R. S. Osorio
  • F. M. Elahi
  • L. Mosconi
  • M. J. de Leon
Review Article


Often viewed as a potential tool for preclinical diagnosis in early asymptomatic stages of Alzheimer’s disease (AD), the term “endophenotype” has acquired a recent popularity in the field. In this review, we analyze the construct of endophenotype—originally designed to discover genes, and examine the literature on potential endophenotypes for the late-onset form of AD (LOAD). We focus on the [18F]-fluoro-2-deoxyglucose (FDG) PET technique, which shows a characteristic pattern of hypometabolism in AD-related regions in asymptomatic carriers of the ApoE E4 allele and in children of AD mothers. We discuss the pathophysiological significance and the positive predictive accuracy of an FDG-endophenotype for LOAD in asymptomatic subjects, and discuss several applications of this endophenotype in the identification of both promoting and protective factors. Finally, we suggest that the term “endophenotype” should be reserved to the study of risk factors, and not to the preclinical diagnosis of LOAD.


Alzheimer’s disease FDG-PET Endophenotype Preclinical Diagnosis Genetics 


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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Emmanuel H. During
    • 1
  • R. S. Osorio
    • 1
    • 2
  • F. M. Elahi
    • 3
    • 4
  • L. Mosconi
    • 1
  • M. J. de Leon
    • 1
    • 5
  1. 1.Center for Brain Health, Silberstein Alzheimer’s InstituteCenter of Excellence on Brain Aging at NYU Langone Medical Center, NYU School of MedicineNew YorkUSA
  2. 2.Alzheimer’s Disease Research UnitCIEN Foundation-Carlos III Institute of Health, Alzheimer Center ReinaMadridSpain
  3. 3.Department of NeurologyUniversity of California, Los Angeles (UCLA)Los AngelesUSA
  4. 4.Wellcome Trust Centre for Human GeneticsUniversity of OxfordOxfordUK
  5. 5.Nathan Kline InstituteOrangeburgUSA

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