注意缺陷多动障碍（ADHD）是一种在儿童期常见的高度遗传性精神行为异常疾病。虽然近年来磁共振成像（MRI）对ADHD儿童脑结构及功能的研究发现了许多与该病行为紊乱明显相关的脑区，然而涉及ADHD深层发病机制的研究却并不多。多巴胺缺陷理论在ADHD病因学中一直占有重要地位。多巴胺递质系统中的儿茶酚胺氧位甲基转移酶（COMT）基因多态性与ADHD的发生具有密切关系，COMT基因多态性可以通过调控多巴胺递质浓度从而影响人类的行为与认知，对研究发病机制意义重大。然而目前结合基因遗传学的ADHD影像研究工作还比较缺乏。本研究拟从基因遗传学角度整合多模态MRI成像脑网络研究手段（包括静息态独立成分分析、弥散张量成像及静息态功能成像图论分析），探索COMT基因变异如何调控ADHD儿童脑网络，进一步揭示ADHD患儿大脑MR改变、行为异常与基因变异之间的复杂联系，以期待促进在ADHD临床治疗上的新突破。

Attention deficit hyperactivity disorder (ADHD) is a common and highly heritable childhood-onset psychiatric disorder. Although structural and functional neuroimaging studies have revealed abnormalities in various brain regions, few studies implicate profound etiological contribution. The dopamine hypothesis has been playing an important role in the etiology of ADHD. The catechol-O-methyltransferase (COMT) gene polymorphism is of particular interest for ADHD as its crucial role in the modulation of dopamine concentration on human behaviour and cognition. However, few evidences implicate involvement of dopamine genetic variances and the altered brain structure and function in the pathomechanism of ADHD in previous studies. Here, we use network based analysis (including independent component analysis, graph theory analysis on diffusion tensor imaging and rest-stating functional MRI) to investigate how COMT genetic variances modulate the brain networks of childhood ADHD. Multi-modal MRI studies combined genetic factors in child ADHD are establishing a platform of knowledge and methods to investigate associations among altered brain networks, behaviour abnormality and genetic variances that offer promise for future therapeutic practice.