ABSTRACT
Objective To examine the association between the polymorphisms of brain-derived neurotrophic factor (BDNF)gene with heroin dependence.Methods Genomic DNA was isolated from the venous blood leukocytes of 308 unrelated patients with heroin dependence and 31 7 healthy individuals.Seven single nucleotide polymorphisms (SNPs)were genotyped using MassARRAY system.Data were analyzed using HaploView 4.0 and SPSS 20.0 software.Results There was a significant difference in the genotype frequency of rs6265 between heroin dependence group and healthy control group (χ2 =1 5.1 5 1,P =0.001).The rs6265 G allele was significantly higher than in controls (χ2 =9.864,P =0.002,OR =1.429,95% CI =1.143 -1.786).Furthermore,there was also a significant difference in the genotype frequency of rs13306221 between heroin dependence group and control group (χ2 =7.699,P =0.006).The rs13306221 G allele was significantly higher than in controls (χ2 =7.137,P =0.008,OR =0.539,95% CI =0.340-0.853).Strong linkage disequilibrium (LD)was observed in one block (D’> 0.9;r 2 >0.8),and significantly less G-G haplotype frequency of block 1 (χ2 =4.546;P =0.033)was found in heroin dependence group. Conclusion Our findings support the role of BDNF rs6265 and rs13306221 polymorphisms in heroin dependence and may guide future studies to identify other genetic risk factors for heroin dependence.