Department of Preventative Medicine, School of Medicine, Kyungpook National University, Daegu, Korea.
Environ Health Perspect. 2010 Mar;118(3):370-4. doi: 10.1289/ehp.0901131. Epub 2009 Nov 6.
Global DNA methylation levels have been reported to be inversely associated with blood levels of persistent organic pollutants (POPs), xenobiotics that accumulate in adipose tissue. Whether these associations extend to a population with much lower concentrations of POPs is not known.
This study was performed to examine whether low-dose exposure to POPs was associated with global DNA hypomethylation in Koreans.
The amount of global DNA hypomethylation was estimated by the percent 5-methyl-cytosine (%5-mC) in Alu and LINE-1 assays in 86 apparently healthy Koreans. Among various POPs, organochlorine (OC) pesticides, polychlorinated biphenyls (PCBs), and polybrominated diphenylethers (PBDEs) were measured.
Most OC pesticides were inversely and significantly associated with %5-mC in the Alu assay, with correlation coefficients in the range 0.2 to 0.3 after adjusting for age, sex, body mass index, smoking, and alcohol. The strongest OC pesticide associations with %5-mC in the Alu assay were observed with oxychlordane, trans-nonachlor, and p,p -dichlorodiphenyldichloroethylene. The correlation coefficient of age with %5-mC in the Alu assay was 0.24, similar to correlations of OC pesticides with %5-mC in the Alu assay. Most PCBs and PBDEs showed nonsignificant inverse trends with %5-mC in the Alu assay, but for some PCBs the U-shaped association was significant. On the other hand, POPs were not associated with %5-mC in the LINE-1 assay.
We found that low-dose exposure to POPs, in particular OC pesticides, was associated with global DNA hypomethylation in apparently healthy Koreans.
已有研究报道，全球 DNA 甲基化水平与血液中持久性有机污染物（POPs）水平呈负相关，POPs 是一类蓄积于脂肪组织中的外源性化学物质。但目前尚不清楚这些关联是否适用于 POPs 浓度低得多的人群。
本研究旨在探讨低剂量 POPs 暴露是否与韩国人群的全基因组低甲基化有关。
本研究共纳入 86 名健康的韩国人，采用 Alu 和 LINE-1 检测法估计全基因组低甲基化的程度，并用该法检测 5- 甲基胞嘧啶（%5-mC）的含量。在各种 POPs 中，有机氯农药（OCs）、多氯联苯（PCBs）和多溴联苯醚（PBDEs）的含量均有检测。
在调整年龄、性别、体重指数、吸烟和饮酒等因素后，大多数 OCs 与 Alu 检测法中的%5-mC 呈显著负相关，相关系数在 0.2 到 0.3 之间。在 Alu 检测法中，与%5-mC 相关性最强的 OCs 是氧氯丹、反式-十氯酮和 p,p′-二氯二苯二氯乙烯。Alu 检测法中，%5-mC 与年龄的相关系数为 0.24，与 OCs 与%5-mC 的相关性相似。大多数 PCBs 和 PBDEs 与 Alu 检测法中的%5-mC 呈非显著负相关，但部分 PCB 呈 U 型关联。另一方面，POPs 与 LINE-1 检测法中的%5-mC 无关。
本研究发现，低剂量 POPs 暴露，尤其是 OCs 暴露，与韩国健康人群的全基因组低甲基化有关。
