催产素（OXT）对人类社会认知和行为的调节作用是目前的研究热点。外源性鼻喷OXT能够增加社会认知相关脑区的激活程度；OXT受体（OXTR）的多态性广泛地影响各种社会行为和认知。此外，OXTR基因变异增加孤独症的发病风险。但是上述神经机制的研究均是基于单个位点的结果，没有考虑基因间的联合及交互作用，且影像模态单一。申请人在已发表的前期工作中发现OXTR的基因多态性影响脑结构及功能，本项目针对6000例大样本的青年健康志愿者拟利用多模态MRI技术，采用多基因风险分数、广义多因子降维法以及中介效应分析，探讨OXT通路上的三个重要基因（OXT、OXTR及CD38）单核苷酸多态性的联合效应及基因间的交互效应对脑结构、功能及对个体奖赏依赖人格的影响。对上述问题的回答将有助于明确OXT通路基因变异对正常人体社会认知影响的神经机制，有重要的潜在临床及转化医学意义。

Recently, an increasing number of research teams play attention to the influence of oxytocin (OXT) on human social recognition and social behavior. Intranasal OXT increases the activity of social brain regions and improves the individual’s performance of social recognition. OXT related gene (OXTR) polymorphisms intensively impact a broad range of social behavior and recognition. Moreover, OXTR gene variations appear to contribute to autism with the key symptom of social dysfunction. But all the researches about the underlying mechanisms are only based on the results of one single nucleotide polymorphism and single MRI modality, regardless of the joint effect and interaction of gene and gene. Our prior study found the impact of OXTR on the brain structure and function. We further investigate the impact of the join effect and interaction of the most important genes (OXT, OXTR and CD38) on oxytocin pathway on brain structure, function and reward-dependence personality based on 6000 young healthy subjects by using the three methods of polygenic risk score, generalized multifactor dimensionality reduction and mediation analysis. This study may improve our understanding of the neural mechanisms of the oxytocin pathway gene variation on individual difference of social recognition and these gene-temperament associations also have potential translational relevance and may become useful as a source of inter-individual variation to oxytocinergic stimulation.