早期成长逆境与多种健康问题的终身风险密切相关。课题组前期研究提示：童年期虐待、家庭社会经济地位不良等多种形式的逆境与青春期发育提前存在关联，与国外不同文化与遗传背景人群研究结论较为一致。结合文献复习和课题组近期发现的持续留守经历青少年端粒长度明显缩短的线索，本课题提出“早期成长逆境致青春期发育提前和生物学老化加速假说”，基于已建立的幼儿队列和农村留守儿童队列，前瞻性、多维度（亲子分离、威胁性和慢性剥夺性）评估早期成长环境，随访男女童第二性征发育，借助两种生物学老化指标（端粒长度、基于DNA甲基化模式的表观遗传学年龄），比较不同逆境经历的同龄个体青春期发育和生物学老化指标的差异，探讨早期成长逆境类型对青春期发育进程、生物学老化速度的预测效应。课题结果将为儿童少年发育与健康的环境病因及其生物学嵌入机制研究开拓新视角，也为早期干预成长逆境终身健康危害效应提供理论框架。

Early life adversity is closely related with multiple health problems across the lifespan. Researches from our team suggested consistent association between various forms of early adversity with early pubertal development, including childhood abuse, household socioeconomic disadvantage. These results were consistent with other studies under different culture and genetic background. Based on literature review and recent progress suggesting correlation between left-behind experiences with telomere shortening, we propose the accelerating effects of early life adversity on pubertal development and biological aging as a possible hypothesis. Prospective and multi-dimensional (maternal separation, threaten and chronic deprivation) assessment of early growing environment will be collected among participants from established kindergarten cohort and left-behind child cohort. All the participants will be followed up with pubertal maturatiom and biological aging process. Age-matched peers with different adversity background will be compared with pubertal development and biological age which is assessed through telomere length and epigenetic age computed from genomic DNA methylation. This project is expected to shed lights on different effects of three dimensions of early life adversity on pubertal tempo and biological aging pace. Results will provide new perspectives on environmental effects on growth and development and underlying embedding mechanisms, as well as theoretical framework for future intervention aiming at preventing or reducing long-term adverse health effects of early life adversity.