Tombeau Cost K, Unternaehrer E, Plamondon A, Steiner M, Meaney M, Atkinson L, Kennedy J L, Fleming A S
Department of Psychology, University of Toronto Mississauga, Mississauga.
Fraser Mustard Institute for Human Development, Toronto.
Genes Brain Behav. 2017 Feb;16(2):285-295. doi: 10.1111/gbb.12337. Epub 2016 Oct 21.
Animal and human studies suggest that initial expression of maternal behaviour depends on oxytocin and dopamine systems. However, the mechanism by which these systems affect parenting behaviours and the timing of these effects are not well understood. This article explores the role of mothers' executive function in mediating the relation between oxytocin and dopamine gene variants and maternal responsiveness at 48 months post-partum. Participants (n = 157) were mothers recruited in the Maternal Adversity, Vulnerability and Neurodevelopment Study, which assesses longitudinally two cohorts of mothers and children in Canada. We examined single nucleotide polymorphisms (SNPs) related to the dopamine and oxytocin systems (DRD1 rs686, DRD1 rs265976, OXTR rs237885 and OXTR rs2254298), assessed mothers' decision-making at 48 months using the Cambridge Neurological Automated Testing Battery (CANTAB) and evaluated maternal responsiveness from videotaped interactions during the Etch-A-Sketch co-operation task. Mediation analyses showed that OXTR rs2254298 A-carriers had an indirect effect on positive parenting which was mediated by mothers' performance on decision-making task (estimate = 0.115, P < 0.005), while OXTR rs2254298 A-carriers had both direct and indirect effects on physically controlling parenting, also mediated through enhanced performance on decision-making (estimate = -0.059, P < 0.005). Dopamine SNPs were not associated with any measure of executive function or parenting (all P > 0.05). While oxytocin has previously been associated with only the early onset of maternal behaviour, we show that an OXTR polymorphism is involved in maternal behaviour at 48 months post-partum through mothers' executive function. This research highlights the importance of the oxytocin system to maternal parenting beyond infancy.
动物和人类研究表明，母性行为的初始表现取决于催产素和多巴胺系统。然而，这些系统影响养育行为的机制以及这些影响的时间尚不清楚。本文探讨了母亲执行功能在介导催产素和多巴胺基因变异与产后48个月时母亲反应性之间关系中的作用。参与者（n = 157）是在“母亲逆境、脆弱性和神经发育研究”中招募的母亲，该研究纵向评估了加拿大的两组母亲和儿童。我们检查了与多巴胺和催产素系统相关的单核苷酸多态性（SNP，即DRD1 rs686、DRD1 rs265976、OXTR rs237885和OXTR rs2254298），使用剑桥神经自动化测试组（CANTAB）评估了母亲在48个月时的决策能力，并通过在“etch-a-sketch”合作任务期间的录像互动评估了母亲的反应性。中介分析表明，携带OXTR rs2254298 A等位基因的个体对积极养育有间接影响，这是由母亲在决策任务中的表现介导的（估计值 = 0.115，P < 0.005），而携带OXTR rs2254298 A等位基因的个体对身体控制型养育既有直接影响也有间接影响，同样通过决策能力的提高介导（估计值 = -0.059，P < 0.005）。多巴胺SNP与任何执行功能或养育指标均无关联（所有P > 0.05）。虽然催产素以前仅与母性行为的早期开始有关，但我们表明，一种OXTR多态性通过母亲的执行功能参与了产后48个月时的母性行为。这项研究强调了催产素系统对婴儿期后母亲养育的重要性。
