Different brain activity in pons in adolescent males with high- and low- activity MAOA genotype: resting-state fMRI study

Abstract

Objective To examine the effects of a functional polymorphism of the monoamine oxidase A (MAOA) gene on spontaneous brain activity in healthy male adolescents. Methods Resting-state fMRI was performed on 31 healthy male adolescents with the low-activity MAOA genotype (MAOA-L) and 25 healthy male adolescents with the high-activity MAOA genotype (MAOA-H). The amplitude of low-frequency fluctuation (ALFF) of the blood oxygen level-dependent (BOLD) signal was calculated using REST software, and was compared between two genotype groups. The region ROIs showed significant difference. The ALFF data in ROIs were related to BIS scores. Results Compared with the MAOA-H group, the MAOA-L group showed a significant decrease of ALFF (P<0.001) in the pons (MNI coordinates: –6, –19, –23; 6, –16, –17; –6, –25, –32). In addition, the BIS scores were positively correlated with ALFF in pons in the MAOA-L group (r=0.398, P=0.02), but not in the MAOA-H group. Conclusions There exists relevance between the polymorphism of MAOA and the spontaneous brain activity in pons.And the lower activity of spontaneous brain activity in pons may be a key risk factor for impulsivity and aggression. Key words: Monoamine oxidase A gene; Amplitude of low-frequency fluctuation; Functional magnetic resonance imaging