Department of Psychiatry, Faculty of Medicine, McGill University, Montreal, QC, Canada.
School of Public Health, University of Saskatchewan, Saskatoon, SK, Canada.
Transl Psychiatry. 2019 Feb 4;9(1):68. doi: 10.1038/s41398-019-0412-y.
There has been a limited number of systematic reviews conducted to summarize the overview of the relationship between DNA methylation and depression, and to critically appraise the roles of major study characteristics in the accuracy of study findings. This systematic review aims to critically appraise the impact of study characteristics on the association between DNA methylation and depression, and summarize the overview of this association. Electronic databases and gray literatures until December 2017 were searched for English-language studies with standard diagnostic criteria of depression. A total of 67 studies were included in this review along with a summary of their study characteristics. We grouped the findings into etiological and treatment studies. Majority of these selected studies were recently published and from developed countries. Whole blood samples were the most studied common tissues. Bisulfite conversion, along with pyrosequencing, was widely used to test the DNA methylation level across all the studies. High heterogeneity existed among the studies in terms of experimental and statistical methodologies and study designs. As recommended by the Cochrane guideline, a systematic review without meta-analysis should be undertaken. This review has, in general, found that DNA methylation modifications were associated with depression. Subgroup analyses showed that most studies found BDNF and SLC6A4 hypermethylations to be associated with MDD or depression in general. In contrast, studies on NR3C1, OXTR, and other genes, which were tested by only few studies, reported mixed findings. More longitudinal studies using standardized experimental and laboratory methodologies are needed in future studies to enable more systematical comparisons and quantitative synthesis.
已有少量系统评价对 DNA 甲基化与抑郁之间的关系进行了总结，并批判性地评估了主要研究特征对研究结果准确性的作用。本系统评价旨在批判性地评估研究特征对 DNA 甲基化与抑郁之间关联的影响，并总结该关联的概述。截至 2017 年 12 月，我们检索了电子数据库和灰色文献中使用抑郁症标准诊断标准的英文研究。本综述共纳入了 67 项研究，并总结了其研究特征。我们将研究结果分为病因学和治疗学研究。这些选定的研究大多是最近发表的，来自发达国家。全血样本是最常研究的常见组织。所有研究均广泛使用亚硫酸氢盐转换，以及焦磷酸测序来检测 DNA 甲基化水平。在实验和统计方法学以及研究设计方面，研究之间存在高度异质性。根据 Cochrane 指南的建议，应进行无荟萃分析的系统评价。本综述总体上发现 DNA 甲基化修饰与抑郁有关。亚组分析表明，大多数研究发现 BDNF 和 SLC6A4 过度甲基化与 MDD 或一般抑郁症有关。相比之下，仅少数研究测试的 NR3C1、OXTR 和其他基因的研究报告了混合结果。未来的研究需要更多使用标准化实验和实验室方法学的纵向研究，以便能够进行更系统的比较和定量综合。
