Association of monoamine oxidase A variable number of tandem repeats and child abuse with aggressive behavior among Chinese adolescents

Abstract

Objective The association of MAOA-VNTR monoamine oxidase A variable number of tandem repeats genotype and child abuse on aggressive behavior among Chinese Han adolescents were examined. Methods A group of 513 (M:367, F:146) 13-18 years old Chinese adolescents were selected randomly, and the effects of child maltreatment ［measured using the child trauma questionnaire (CTQ)］ and aggressive behavior during adolescents′ period ［assessed by the Child Behavior Checklist for Youth Self-Report (YSR)］ were examined respectively. DNA were collected and MAOA-VNTR genotype were assessed via venous blood sample. Both the main effects of MAOA genotype, children′s maltreatment experience and the interaction between them were analyzed by a linear regression analysis. Results In all, 513 middle school students (367 boys, 146 girls) were analyzed in the study. The mean aggression scores were (10.13±6.67) and (9.18±6.36) for boys and girls. The low and high activity of MAOA-VNTR genotype accounts for 58.3% and 41.7% for boys, and 39.4% and 22.5% for girls respectively. The GLM model showed that there were no direct association between the MAOA genotypes with aggression scores, while a significant association between children′s maltreatment experience with aggressive behavior in adolescents′ period were found for both boys and girls (P<0.01). Some significant interactions between MAOA genotype with subtypes of maltreatment were uncovered (boys: P=0.02, P<0.01 and P=0.04 for MAOA with physical abuse, emotional abuse and sexual abuse; girls: P= 0.03 and P=0.04 for MAOA with sexual and emotional abuse). For adolescents with the low activity of MAOA-VNTR were more prone to commit aggressive behavior when suffered children′s abuse for both gender. Conclusions Aggressive behaviors among Chinese adolescents may be affected by a gene-enviornment interaction involving MAOA-VNTR and children′s abuse experience which may be differentially sensitive to the subtype of childhood maltreatment and gender. Key words: Monoamine oxidase; Polymorphism single nucleotide; Child abuse; Aggression