Department of Psychiatry, Tulane University, New Orleans, LA, USA.
Mol Psychiatry. 2012 Jul;17(7):719-27. doi: 10.1038/mp.2011.53. Epub 2011 May 17.
Accelerated telomere length attrition has been associated with psychological stress and early adversity in adults; however, no studies have examined whether telomere length in childhood is associated with early experiences. The Bucharest Early Intervention Project is a unique randomized controlled trial of foster care placement compared with continued care in institutions. As a result of the study design, participants were exposed to a quantified range of time in institutional care, and represented an ideal population in which to examine the association between a specific early adversity, institutional care and telomere length. We examined the association between average relative telomere length, telomere repeat copy number to single gene copy number (T/S) ratio and exposure to institutional care quantified as the percent of time at baseline (mean age 22 months) and at 54 months of age that each child lived in the institution. A significant negative correlation between T/S ratio and percentage of time was observed. Children with greater exposure to institutional care had significantly shorter relative telomere length in middle childhood. Gender modified this main effect. The percentage of time in institutional care at baseline significantly predicted telomere length in females, whereas the percentage of institutional care at 54 months was strongly predictive of telomere length in males. This is the first study to demonstrate an association between telomere length and institutionalization, the first study to find an association between adversity and telomere length in children, and contributes to the growing literature linking telomere length and early adversity.
端粒长度的加速损耗与成年人的心理压力和早期逆境有关;然而,目前还没有研究表明儿童时期的端粒长度是否与早期经历有关。布加勒斯特早期干预项目是一项独特的随机对照试验,比较了寄养与继续在机构中护理。由于研究设计,参与者经历了量化的机构护理时间范围,并且代表了一个理想的人群,可以研究特定的早期逆境、机构护理和端粒长度之间的关联。我们研究了平均相对端粒长度、端粒重复拷贝数与单基因拷贝数的比值(T/S)与机构护理暴露之间的关联,机构护理暴露被量化为每个孩子在基线(平均年龄 22 个月)和 54 个月时在机构中生活的时间百分比。T/S 比值与时间百分比之间存在显著的负相关。在童年中期,暴露于机构护理时间较长的儿童的相对端粒长度明显较短。性别修饰了这种主要效应。基线时在机构中护理的时间百分比显著预测了女性的端粒长度,而 54 个月时机构护理的时间百分比强烈预测了男性的端粒长度。这是第一项研究表明端粒长度与机构化之间存在关联的研究,也是第一项研究表明逆境与儿童端粒长度之间存在关联的研究,并为越来越多的将端粒长度与早期逆境联系起来的文献做出了贡献。