中文摘要：

有研究提示电磁暴露可能是白血病发病的潜在危险因素。为探讨对讲机产生的电磁暴露对Wif-1基因甲基化水平及血液中白细胞构成的影响,采用1：1配对设计,选择年龄匹配的60名男性作为研究对象,最终纳入分析的为对讲机使用组（暴露组）29名,非使用组（对照组）28名。采用自行设计的流行病学调查问卷收集研究对象的一般人口学特征及职业暴露情况等。采用美国SEQUENOM Mass Array？Epi TYPER技术平台检测Wif-1基因的甲基化水平。采用配对t检验和多因素混合效应模型分析对讲机使用和Wif-1基因甲基化水平,以及Wif-1基因甲基化水平和血液中白细胞构成的关系。研究结果显示：在Wif-1基因启动子区域的32个CpG位点中,7个位点（CpG7、CpG8、CpG12、CpG16、CpG21、CpG28和CpG31）的甲基化水平暴露组显著高于对照组;电磁暴露与Wif-1基因平均甲基化水平呈正相关（偏回归系数β=2.19,概率P=0.026）。而Wif-1基因甲基化水平与淋巴细胞百分比呈正相关（β=0.633,P=0.020）,与嗜酸性粒细胞百分比呈负相关（β=-0.151,P=0.016）。结果表明电磁暴露可能通过调节Wif-1基因甲基化水平而影响血液中淋巴细胞的构成,因而遗传的改变可能是电磁暴露致癌的重要机制,但是还需要更大样本量的研究来进一步确认。

英文摘要：

Electromagnetic fields （EMF） have been identified as a potential hazard to leukemia. To explore the effects of EMF from walkie talkies on the methylation of Wnt inhibitory factor-1 （Wif-1） gene promoter and the proportion of white blood cells, 60 male samples based on whether walkie talkies exposed, matched by age, were selected by 1：1 paired design from previous cross-section study. A total of 29 males with and 28 without walkie talkies use were enrolled in final analyses. A questionnaire and physical examination were applied to obtain relevant information. Quantitative DNA methylation analysis was carried out by SEQUENOM assay. Paired Student＇s t-test and multivariable linear regression of mixed model were used to explore the associations of walkie talkies with methylation of Wif-1 gene promoter, and the methylation level of Wif-1 with the proportions of white blood cells. Out of 32 CpG sites analyzed in Wif-1 gene promoter, seven sites including CpG7, CpG8, CpG12, CpG16, CpG21, CpG28 and CpG31 had a significant increased level of methylation in the exposure group; and electromagnetic exposure was associated with an increased average methylation level （partial regression coefficent,β=2.19, probability P=0.026）. Additionally, the average level of Wif-1 methylation was significantly related with an increased proportion of lymphocytes （β=0.633, P=0.020） while a decreased proportion of eosimophils （ β= -0.151, P=0.016）. The present study suggests that electromagnetic fields might raise the proportion of lymphocytes via altering the methylation level of Wif-1 gene promoter. Epigenetic changes may be the important mechanism for the carcinogenic of EMF.