1对同卵双生新生儿DNA甲基化谱差异分析  

A study of differential DNA methylation profile between two new born monozygotic twins

作　　者：李淑瑾[1] 关亚卿[1] 张贺玲[2] 付丽红[1] 张晓静[1] 马春玲[1] 丛斌[1] 

机构地区：[1]河北医科大学法医学系河北省法医学重点实验室,河北石家庄050017 [2]石家庄市妇产医院,河北石家庄050000

出　　处：《中国法医学杂志》2012年第4期299-302,共4页Chinese Journal of Forensic Medicine

基　　金：国家自然科学基金(30973364)

摘　　要：目的探索1对同卵双生新生儿之间DNA甲基化谱的差异。方法应用甲基化免疫共沉淀结合高通量测序法对1对同卵双生新生儿的DNA甲基化谱进行检测,分析基因组DNA甲基化特点及其之间的差异,筛选适用于法医学分析的甲基化位点。结果两样本各获得7 300万原始测序序列(raw reads)数据,与人类基因组参考序列比对,各得到4 800万和5 000万唯一比对reads,其中大部分分布在重复区域,且在Alu序列分布最为广泛。两样本DNA甲基化富集区域(peak)各检测到257 362条和197 272条,基因组覆盖率分别为6.53%和5.29%,分布在基因组不同区域,以中间内含子区含量最多。分析两样本甲基化差异区域得到2 205条差异的甲基化序列,其中595条位于基因区域,1 610条位于基因间区,从中筛选出113条序列,用于进一步深入研究其法医学应用价值。结论本研究初步证实了DNA甲基化用于同卵双生子鉴定的可行性,为筛选同卵双生子DNA甲基化差异位点提供了基础数据。Objective In this study we mapped DNA methylation profile of a pair of new born MZ twins,hoping to discover some different regions for forensic analysis.Methods Genome DNA was extracted from cord blood of a pair of confirmed new born MZ twins.DNA methylation profile was obtained by using methylated DNA immunoprecipitation sequencing（MeDIP-seq）.Results According to the MeDIP-seq results,3.6Gb data containing 73 million reads was obtained for each sample.By mapping onto the human genome reference,each sample got 48 million and 50 million unambiguous reads respectively.The reads covered 33.25% and 38.76% of the genome and appeared in every gene region,and the maximum number of reads was in repeat elements.Among the repeat elements,the SINE/Alu sequence was the most widely distribution area.Peak information showed that 257 thousand and 197 thousand peaks were obtained for each sample,covered 6.53% and 5.29% in the genome.These peaks had a widely distribution among gene regions but had a maximum number in the internal introns.Totally,we found 2 205 different DNA methylation regions through whole genome between the two MZ individuals,595 located in the gene regions and 1 610 in the internal gene regions.From all of these regions,we finally selected 113 regions as markers for following forensic study.Conclusion This study showed probability of DNA methylation in identifying MZ twins and finally selected 113 different DNA methylation regions for further study for the forensic application.

关 键 词：法医遗传学 DNA甲基化谱 甲基化免疫共沉淀 同卵双生子 高通量测序 

分 类 号：D919[医药卫生—法医学]