Investigating the association of Val/Met polymorphism of the BDNF gene with the incidence of disease in patients with Alzheimer and comparison with healthy elderly people in Iran

Alzheimer's disease is the most common cause of dementia in the elderly and the genetic and environmental factors interfere with its creation. The BDNF gene is responsible for producing a brain-derived neuronal factor. In this disease, the valine66methionine polymorphism and nucleotide changes of 196 (G>A) BDNF are genetic risk factors .This polymorphism has not been investigated in patients with Alzheimer's disease in Iran. This study aimed to provide appropriate information on the prognosis of the disease and the ability to get it. In this case-control study, 73 patients with Alzheimer's disease and 100 healthy controls were evaluated. Blood samples were taken from the subjects and DNA was extracted. After quantitative and qualitative DNA analysis, PCR-RFLP was performed and the results of both groups were analyzed and compared. Fourteen patients and seven controls had polymorphisms of BDNF gene. Fifty-nine patients had normal allele, 8 patients with heterozygote allele and 6 patients had methionine/methionine allele. In the controls, 93 patients had normal allele, 5 with heterozygote allele and 2 had methionine/methionine allele. The findings of this study indicate that the increase in valine/methionine polymorphism in the BDNF gene in Alzheimer's patients compared to the control group can express the role of this polymorphism in this disease. Also, patients with this polymorphism had a worse clinical status than patients without this polymorphism. Therefore, evaluation of this polymorphism can provide appropriate information about the patient's condition.