DNA羟甲基化在环境流行病学中的研究进展

Research progress on DNA hydroxymethylation in environmental epidemiology

5-羟甲基胞嘧啶(5hmC)是TET(ten-eleven translocation)蛋白通过氧化5-甲基胞嘧啶(5mC)产生的一种修饰碱基。近年来的研究发现,5hmC不仅是DNA主动去甲基化的中间产物,也可作为一种稳定的表观遗传标记,在环境与疾病之间发挥"桥梁"作用。环境因素可以通过影响基因组5hmC的模式参与调控疾病的发生发展,且5hmC在指示某些外界环境因素暴露导致的健康效应变化方面可能比5mC更加敏感。因此,研究5hmC在环境暴露到疾病发生这个连续过程中的分布变化,对阐明疾病的发生发展规律,开发早期诊断技术和发现有效干预靶点具有重要意义。本文以5hmC为中心,对环境因素致5hmC改变的研究现状以及5hmC与慢性疾病的研究进展进行简要综述。

5-hydroxymethylcytosine(5hmC) is a major oxidation product of 5-methylcytosine(5 mC) catalyzed by ten-eleven translocation(TET) enzymes. Recent studies have revealed that 5hmC is not only an intermediate of active DNA demethylation, but also a stable epigenetic marker that could act as a bridge between environmental exposure and disease outcomes. Exposure to environmental factors can regulate the occurrence and development of diseases by affecting the pattern of genomic 5hmC, while 5hmC may be more sensitive than 5mC in reflecting the health effects caused by exposure to some external environmental factors. Therefore, it is critical to uncover the roles of 5hmC in the associations between environmental exposure and disease outcomes, in order to clarify the underlying mechanisms of the occurrence and development of diseases, develop early diagnostic techniques, and identify effective intervention targets. In the present study, we reviewed the published literature reporting the effects of environmental factors on 5hmC, as well as the associations between 5hmC and chronic diseases.