Investigation of the relationship between alzheimer's type dementia and microrna polymorphisms regulating the BDNF (brain inherited neurotrophic factor) gene

INVESTIGATION OF THE RELATIONSHIP BETWEEN ALZHEIMER'S TYPE DEMENTIA AND MICRORNA POLYMORPHISMS REGULATING THE BDNF (BRAIN INHERITED NEUROTROPHIC FACTOR) GENE Tuna A. Aydın Adnan Menderes University, Health Sciences Institute, Molecular Biotechnology Program, Master Thesis, Aydın, 2023. Objective: Alzheimer's type dementia is a neurodegenerative disease associated with neuronal loss and defects. Brain-Derived Neurotrophic Factor (BDNF) plays a crucial role in the survival and function of neurons and has been linked to neurodegenerative diseases, including Alzheimer's. MicroRNAs (miRNAs) are small, non-coding RNA molecules that play a vital role in regulating gene expression, including the BDNF gene. Accumulating evidence suggests that BDNF synthesis may be influenced by miRNAs, establishing a regulatory negative feedback loop between BDNF and miRNAs. Therefore, the aim of our research is to investigate miRNA polymorphisms regulating the BDNF gene in patients with Alzheimer's type dementia. Materials and Methods: The study included 70 patients with Alzheimer's type dementia and 70 healthy individuals of the same age group without any other neurodegenerative diseases, who visited the Psychiatry Clinic of Aydın State Hospital. Genotyping with reactive agents in nanoliter volumes was performed using Integrated Fluidic Circuit (IFC)-based BioMark technology. The SNPType Panel developed by Fluidigm was used to examine five related miRNA regions in the DNA samples of our patient and control groups. Results: There was no statistically significant difference in gender and age between the Alzheimer's type dementia and control groups. A comparative analysis of the Alzheimer's type dementia group and the control group revealed statistically significant differences in the genotypic distribution of miR-206, miR-30e, and miR-26b polymorphisms, as well as the allele frequencies of miR-30e and miR-206 polymorphisms (p <0.05). Conclusion: The potential findings of our research could provide insights into the mechanisms of Alzheimer's type dementia and contribute to identifying Alzheimer's predisposition and distinguishing dementia subtypes using miRNA polymorphisms as biomarkers. Furthermore, investigating the relationship between miRNAs and BDNF may lead to the development of targeted therapeutic interventions with prophylactic effects against Alzheimer's disease at a molecular level. Keywords: Alzheimer type dementia, Alzheimer's disease, BDNF gene, miRNAs regulating the BDNF gene, SNPType Assay