Potential Protective Role of SDF-1 and CXCR4 Gene Variants in the Development of Dementia

The aim of this study was to evaluate the role of polymorphisms of stromal cell-derived factor-1 (SDF-1) and chemokine receptor-4 (CXCR4) genes in dementia susceptibility in a Turkish population. The study group included 61 dementia patients, while the control group comprised 82 healthy individuals. Gene polymorphisms of SDF-1 3'A G801A (rs1801157) and CXCR4 C138T (rs2228014) were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. A significantly reduced risk for developing dementia was found for the group bearing an A allele for SDF-1 3'A polymorphism (p=0.009; χ =6.812; OR=0.626; 95%CI= 0.429-0.913). The frequency of the CXCR4 TT and TC genotype was significantly lower in patients with dementia compared to controls (p=0.028; χ =5.583; OR=0.215; 95%CI=0.05-0.914); (p=0.027; χ =4.919; OR=0.484; 95% CI=0.246-0.955). Additionally, combined genotype analysis showed that the frequency of SDF1 GA-CXCR4 CC was significantly lower in patients with dementia in comparison with those of controls (p=0.049; OR=0.560; 95% CI= 0.307±1.020). Our study provides new evidence that SDF1 A and CXCR4 T alleles may be associated with a decreased dementia risk. The present study is important because to our knowledge, it is the first one to be conducted in a Turkish population to date, but we believe that more patients and controls are needed to obtain statistically significant results.