足月儿与早产儿脐血有核红细胞基因组DNA甲基化差异分析

Analysis of Genome-Wide DNA Methylation Differences in Umbilical Cord Blood Nucleated Red Blood Cells Between Term and Preterm Infants

目的:采用甲基化基因芯片技术从全基因组水平分析足月儿与早产儿脐血有核红细胞DAN甲基化差异,筛选出可能与γ珠蛋白基因(HBG)表达相关的差异甲基化基因及生物信号通路。方法:收集足月产儿及早产儿各8例,取其脐血标本,分离脐血有核红细胞并提取基因组DNA,并对其进行亚硫酸氢盐转化。利用Illumina 850K甲基化芯片检测2组样本的DNA甲基化位点。筛选差异甲基化位点,并通过GO和KEGG富集分析得到差异甲基化基因的功能。结果:相较于早产组,足月组共筛选到4749个差异甲基化位点,其中低甲基化位点4359个,高甲基化位点390个。GO和KEGG分析结果显示,差异甲基化基因的功能主要涉及造血系统、生长发育过程、Wnt和Notch信号通路等。结论:本研究获得了足月组和早产组脐血有核红细胞在全基因组水平的差异甲基化位点,筛选出可能与γ→β珠蛋白基因表达转换相关的通路和基因。这为后续进一步研究HBG基因的表达调控机制提供了新的研究靶点。

Objective:To analyze the genome-wide DNA methylation differences in umbilical cord blood nucleated red blood cells(NRBCs)between term and preterm infants by using the methylation gene chip technology,and to screen the genes of differential methylation and biological signaling pathways which may be related to the expression ofγ-globin gene(HBG).Methods:Umbilical cord bloods of eight term infants and eight preterm infants were collected,and NRBCs of each sample was isolated,then genome DNA was extracted and bisulfite conversion was performed.The DNA methylation sites were detected by using the Illumina 850K BeadChip.Differential DNA methylation sites were screened,and the function of genes with differential methylation was analyzed by using GO and KEGG enrichment analysis.Results:Compared with the preterm group,4749 differential DNA methylation sites of term group were screened out,including 4359 hypomethylation sites and 390 hypermethylation sites.GO and KEGG analysis indicated that the function of genes with differential methylation mainly involved in the hemopoietic system,growth and development process,Wnt and Notch signal pathways.Conclusion:The differentical methylation sites at genome-wide level in umbilicar cord blood NRBC of term and preterm infants have been obtained,and the signal pathway and genes which possibily related with swiching the expression ofγ-globin gene toβ-globin gene have been screened-out.This study provide the new targets for studing the mechamism regulating expression of HBG gene.