Gene expression analysis in plasma of patients with Alzheimer's disease


  • Seda Kusoglu Gultekin Department of Molecular Biology and Genetics, Uskudar University, Istanbul, Turkey.
  • Irem Gulfem Albayrak Department of Molecular Biology and Genetics, Uskudar University, Istanbul, Turkey.
  • Yunus Diler Neurology Clinic, Umraniye Research and Training Hospital, Istanbul, Turkey.
  • Ayse Destina Yalcin Neurology Clinic, Umraniye Research and Training Hospital, Istanbul, Turkey.
  • Belkis Atasever Arslan Department of Molecular Biology and Genetics, Uskudar University, Istanbul, Turkey.



Alzheimer's disease, Gene expression, mRNA profiling


Alzheimer's disease (AD), which is a neurodegenerative disease, cannot be noticed until severe symptoms are observed. This poses a global challenge as the average human lifespan increases, making it a concern for the entire world population. Early diagnosis can play a crucial role in slowing the progression of the disease, thereby enhancing the quality of life for both the patient and their relatives. AD has been linked to alterations in mRNA expressions. The objective of the presented study was to determine whether there were significant differences in gene expression in blood plasma between Alzheimer's patients and healthy controls. MAPT, APP, Tubb3, TrkB, and CDC42 genes were selected as target genes due to their potential associations with AD. To analyse mRNA expression levels in the control group and AD patients, the real-time PCR (qPCR) method was performed. The findings indicate that MAPT, APP, Tubb3, and CDC42 genes' expression levels were significantly downregulated by 1.09, 1.08, 1.09, and 1.14 times, respectively (p<0.05) in AD patients. Although the TrkB gene expression appeared to be downregulated by 1.03 times in the AD group, it is not statistically different. Given the molecular associations between the pathways of the target genes and AD, changes in the expression of these genes may contribute to the pathogenesis of AD. They may represent potential biomarkers for early diagnosis.


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How to Cite

Gultekin, S. K., Albayrak, I. G., Diler, Y., Yalcin, A. D. and Arslan, B. A. (2024) “Gene expression analysis in plasma of patients with Alzheimer’s disease”, Neuroscience Research Notes, 7(1), pp. 302.1–302.9. doi: 10.31117/neuroscirn.v7i1.302.