Child Psychopathology Unit, Scientific Institute, IRCCS Eugenio Medea, 23842 Bosisio Parini, LC, Italy.
Department of Electronics Information and Bioengineering, Politecnico di Milano, 20133 Milano, MI, Italy.
J Exp Child Psychol. 2022 Jul;219:105413. doi: 10.1016/j.jecp.2022.105413. Epub 2022 Mar 15.
The serotonin transporter promoter region polymorphism (5-HTTLPR) has been implicated in stress regulation, with increased stress reactivity often being found in carriers of the low-expressing short (S) allele. Nevertheless, the role of the 5-HTTLPR in influencing parasympathetic stress reactivity, as indexed by Respiratory Sinus Arrhythmia (RSA), is still unknown. This study examined, for the first time, whether the 5-HTTLPR was associated with variations in RSA response to maternal separation in a sample of 69 healthy 5-year-old children. Preschoolers' RSA was measured during an age-adapted version of the Strange Situation Procedure (SSP). The 5-HTTLPR polymorphism was tested as a predictor of RSA dynamic response to the SSP through multilevel models. A significant interaction between 5-HTTLPR and SSP episodes was found. In particular, whereas a significant decrease in RSA levels was observed during the stranger episode in the whole sample, S allele carriers showed a significant decrease in RSA levels from the stranger episode to the first separation episode, followed by an increase for the rest of the procedure. Albeit preliminary, data support the view that the 5-HTTLPR may contribute to individual differences in RSA stress reactivity from preschool age.
5-羟色胺转运体启动子区域多态性（5-HTTLPR）与应激调节有关，携带低表达短（S）等位基因的个体通常表现出更高的应激反应性。然而，5-HTTLPR 是否影响迷走神经应激反应，如呼吸窦性心律失常（RSA），目前尚不清楚。本研究首次在 69 名健康 5 岁儿童样本中，检查了 5-HTTLPR 是否与母亲分离对 RSA 反应的变化有关。在适应年龄的陌生情境程序（SSP）中测量了学龄前儿童的 RSA。通过多层次模型，将 5-HTTLPR 多态性作为 SSP 对 RSA 动态反应的预测因子进行测试。发现 5-HTTLPR 和 SSP 发作之间存在显著的相互作用。特别是，在整个样本中，陌生人发作时 RSA 水平显著下降，而 S 等位基因携带者的 RSA 水平从陌生人发作到第一次分离发作时显著下降，随后在其余过程中增加。尽管初步的，但数据支持这样一种观点，即 5-HTTLPR 可能有助于个体在学龄前儿童时期的 RSA 应激反应性差异。
