Department of Psychology, McGill University, Montreal, Quebec, Canada.
Department of Psychiatry, Jewish General Hospital, Montreal, Quebec, Canada.
Dev Psychopathol. 2020 May;32(2):511-519. doi: 10.1017/S0954579419000257.
Theory of mind, the ability to represent the mental states of others, is an important social cognitive process, which contributes to the development of social competence. Recent research suggests that interactions between gene and environmental factors, such as oxytocin receptor gene (OXTR) polymorphisms and maternal parenting behavior, may underlie individual differences in children's theory of mind. However, the potential influence of DNA methylation of OXTR remains unclear. The current study investigated the roles of OXTR methylation, maternal behavior, and their statistical interaction on toddlers' early emerging theory of mind abilities. Participants included a community sample of 189 dyads of mothers and their 2- to 3-year-old children, whose salivary DNA was analyzed. Results indicated that more maternal structuring behavior was associated with better performance, on a battery of three theory of mind tasks, while higher OXTR methylation within exon 3 was associated with poorer performance. A significant interaction also emerged, such that OXTR methylation was related to theory of mind among children whose mothers displayed less structuring, when controlling for children's age, sex, ethnicity, number of child-aged siblings, verbal ability, and maternal education. Maternal structuring behavior may buffer the potential negative impact of hypermethylation on OXTR gene expression and function.
心理理论，即代表他人心理状态的能力，是一种重要的社会认知过程，有助于社会能力的发展。最近的研究表明，基因和环境因素之间的相互作用，如催产素受体基因（OXTR）多态性和母亲的养育行为，可能是儿童心理理论个体差异的基础。然而，OXTR 的 DNA 甲基化的潜在影响尚不清楚。本研究调查了 OXTR 甲基化、母亲行为及其统计相互作用对幼儿早期心理理论能力的影响。参与者包括来自社区的 189 对母婴样本，分析了他们的唾液 DNA。结果表明，更多的母亲结构化行为与更好的表现相关，在一系列三个心理理论任务中，而第 3 外显子内的 OXTR 甲基化水平较高与表现较差相关。还出现了一个显著的相互作用，即当控制儿童的年龄、性别、种族、儿童年龄的兄弟姐妹数量、语言能力和母亲教育程度时，OXTR 甲基化与心理理论有关，仅当母亲表现出较少的结构化行为时。母亲的结构化行为可能缓冲了 OXTR 基因表达和功能的过度甲基化的潜在负面影响。
