A Correlational Study Of BDNF (Val66Met) Gene Polymorphisms,Childhood Abuse And Severity Of Depressive Disorder

Objective:To assess the relationship between brain-derived neurotrophic factor gene(BDNF)polymorphism(Val66Met)and childhood abuse in the severity of depressive disorder.Methods:DSM-IV was used as the diagnostic criteria,and 182 patients with depression were enrolled in this study.The severity of depression was assessed on the basis of the HAMD-17 scale and the childhood abuse of the patients was assessed using the Childhood Experience of Care(CECA).The BDNF(Val66Met)genotypes were identified by polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP).Genotype and allele frequency distribution were analyzed by H-W equilibrium,and multiple regression analysis was used to explore the interaction between gene polymorphism and childhood abuse on the severity of depression.All data analysis was done using the SPSS22.0 statistical software.P<0.05 was set as statistically significance.Results:1.There was not statistical significance of the genotype distribution of Met/Met,Val/Met and Val/Val between observed and the expected frequency,and accorded with H-W equilibrium.2.There was not significant differences in the incidence of childhood abuse among the three genotypes.3.There was not significant differences among the three BDNF genotype in patients with HAMD total score and all factors of HAMD.The loss interest in job score of HAMD was significantly different among the three BDNF genotypes(P<0.05),and Met/Met patients were higher than Val/Met and Val/Val.4.Childhood abuse significantly predicted the severity of depression(P<0.05).Depression score was not significantly predicted by the interaction between genotypes and childhood abuse.Conclusion:1.There was no significant association between BDNF Val66 Met polymorphism and the severity of depression in Chinese Han population,the Met carriers may be associated with losing interest which core symptoms of depression.2.Childhood abuse significantly increased the severity of depression.3.The interaction between genotypes and childhood abuse was not significantly predicted the severity of depression.