Doctoral Dissertation Research: DNA Methylation and Human Reproductive Life History

初潮（第一次月经）是一个重要的生殖生活史标志，与生命早期环境和晚年健康风险有潜在联系。本论文的研究项目是在生活史的框架下研究月经初潮，以更好地了解DNA修饰、早期社会心理和能量压力因素与月经初潮年龄之间的关系，以及这些变量对成年生殖激素水平的影响。该项目将有助于增加关于童年环境变量如何直接和间接影响人类生殖生活史轨迹的知识体系，并可能为与月经初潮时间有关的公共卫生研究提供信息。这项研究的结果将与更广泛的科学界共享，该项目将支持一名女研究生的培训和包容性的科学推广工作。像DNA甲基化这样的表观遗传特征被认为是由个体改变的？早期环境。该项目将DNA甲基化作为一种方式来研究，不同的环境可以产生生殖特征的变化，即初潮年龄和成人生殖激素浓度。这项研究是在两个基因相似的人群中进行的，他们生活在不同的早期生活环境中，以分析基因和发育环境对这些生殖特征的不同影响。研究人员将在目前描述童年环境对成年生殖特征影响的概念模型的基础上，探索能量与社会心理压力源更有可能影响初潮年龄的背景。研究人员将测试DNA甲基化和早期压力因素对月经初潮年龄的综合影响，以及所有三个变量对成人激素浓度的影响。

Menarche (first menses) is a critical reproductive life history marker with potential links to early-life environment and later-life health risks. This dissertation research project investigates menarche in a life history framework, to better understand the relationship among DNA modifications, early life psychosocial and energetic stressors, and age at menarche, as well as the effect of these variables on adult reproductive hormone levels. The project will contribute to a growing body of knowledge on the ways that childhood environmental variables directly and indirectly affect human reproductive life history trajectories, and may inform public health research related to the timing of menarche. Results of this study will be shared with the wider scientific community, and the project will support training of a female graduate student and inclusive science outreach efforts. Epigenetic traits like DNA methylation are thought to be modified by an individual?s early environment. This project examines DNA methylation as one way that different environments can produce variation in reproductive traits, namely age at menarche and adult reproductive hormone concentrations. The research is conducted in two genetically similar populations living in different early-life environments, in order to parse the different effects of genes and developmental environments on these reproductive traits. The investigators will explore the contexts in which energetic versus psychosocial stressors are more likely to affect age at menarche, building on current conceptual models that describe the effects of childhood environments on adult reproductive traits. The investigators will test for combined effects of DNA methylation and early stressors on menarcheal age, and for effects of all three variables on adult hormone concentrations.