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

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.