Intergenerational continuation of parent-child separation and 1-year telomere length attrition among mother-offspring dyads in rural China: The moderating effects of resilience

中国农村母子二元组亲子分离代际延续与1年端粒长度损耗：韧性的调节作用

Authors: Kai Ma, Min Zhu, Anhui Zhang, Min Zuo, Yongling Huang, Yuhui Wan, Fangbiao Tao, Ying Sun.

Source: J Affect Disord.024 Sep 19:368:599-606.

doi: 10.1016/j.jad.2024.09.098.

Abstract

Background: Although stressor exposure early in life was known risk factor for telomere length (TL) attrition, limited literature explored it across generations. Furthermore, the effects of resilience have rarely been examined. Here, we examined whether the effects of intergenerational parent-child separation on offspring 1-year TL attrition vary by the levels of resilience.

Method: In a sample of 342 mother-child dyads living in rural China, the intergenerational continuation of parent-child separation was defined as the two generations both experiencing parent-child separation from both parents for >6 months a year early in life assessed by the parent-reported questionnaire, whereas intergenerational discontinuity refers to parent-child separation exposed in one generation only. TL was measured at baseline (from June to November 2021) and 1-year later with children's buccal mucosa swabs, with resilience polygenic risk scores (PRS) evaluated based on 4 single-nucleotide variations in 4 resilience-related genes (OXTR, FKBP5, NPY, and TNF-α).

Results: Among 342 mother-offspring dyads,35(10.2%)experienced intergenerational continuation of parent-child separation, and 139(40.6%)were identified as discontinuous. Remarkably, a 0.12-point reduction in TL attrition was only associated with intergenerational continuation of parent-child separation (95% CI:0.04, 0.21, p＜0.01) but not discontinuity. Importantly, the association between intergenerational continuation of parent-child separation with accelerated TL attrition disappeared in offspring with high resilience PRS (β＝0.07, 95%CI:-0.06, 0.21).

Conclusion: Our findings highlight the importance of breaking the intergenerational cycle of parent-child separation and the moderating effects of resilience on TL attrition for children exposed to adversity.

Keywords: Intergenerational; Parent-child separation; Preschool children; Resilience; Telomeres.

摘要

背景：尽管生命早期应激源暴露是端粒长度（TL）损耗的已知危险因素，但鲜有文献跨代探讨二者关联。此外，弹性的影响也很少被研究。在这里，我们研究了代际亲子分离对后代1年TL损耗的影响是否因弹性水平而异。

方法：在居住在中国农村的342名母子二人组样本中，亲子分离的代际延续定义为父母报告问卷评估的两代人在生命早期每年经历亲子分离＞6个月，而代际不连续性是指仅在一代人中暴露的亲子分离。在基线（2021年6月至11月）和 1 年后用儿童口腔粘膜拭子测量 TL，根据4个弹性相关基因（OXTR、FKBP5、NPY和TNF-α）中的4个单核苷酸变异评估弹性多基因风险评分（PRS）。

结果：在342个母子二对组中，35个（10.2 %）经历了亲子分离的代际延续，139个（40.6 %）被确定为不连续的。值得注意的是，TL损耗减少0.12分仅与亲子分离的代际延续相关（95 % CI：0.04～0.21，P＜0.01），但不连续。重要的是，亲子分离的代际延续与加速TL损耗之间的关联在具有高弹性PRS的后代中消失（β＝0.07，95%CI：-0.06～0.21）。

结论：我们的研究结果强调了打破亲子分离代际循环的重要性以及弹性对逆境儿童TL损耗的调节作用。

关键词：代际；亲子分离；学龄前儿童；心理弹性；端粒