Embryo Biotechnology Lab, Animal Biotechnology Centre, ICAR-National Dairy Research Institute (Deemed University), Karnal, Haryana, 132001, India.
Sci Rep. 2022 Mar 25;12(1):5161. doi: 10.1038/s41598-022-09207-8.
Somatic cell nuclear transfer technique (SCNT) has proved to be an outstanding method of multiplication of elite animals but accompanied with low efficiency and live birth rate of cloned animals. Epigenetic alterations of DNA has been one of the culprits behind this issue. Cloned embryos are found to deviate slightly from regular pattern of demethylation and re-methylation at the time of nuclear reprogramming and embryonic development when compared with embryos produced by in vitro fertilization (IVF). Thus, the present study was aimed at evaluating global DNA methylation profiles of cloned embryos at 2-cell, 8-cell and blastocyst stages and compare it with corresponding stages of embryos produced by IVF by using MeDIP-Sequencing on Illumina-based platform. We found out that cloned embryos exhibited significantly different DNA methylation pattern as compared to IVF embryos with respect to distribution of differentially methylated regions in different components of genome, CpG islands distribution and methylation status, gene ontological profiles and pathways affected throughout the developmental stages. The data generated from MeDIP-Seq was validated at blastocyst stage cloned and IVF embryos by bisulfite-sequencing PCR on five randomly selected gene regions.
体细胞核移植技术（SCNT）已被证明是一种优秀的精英动物繁殖方法，但伴随着低效率和克隆动物的活产率。DNA 的表观遗传改变是导致这一问题的原因之一。与体外受精（IVF）产生的胚胎相比，克隆胚胎在核重编程和胚胎发育时，在去甲基化和重新甲基化的规律上略有偏离。因此，本研究旨在通过 Illumina 平台上的 MeDIP-Seq 方法，评估 2 细胞期、8 细胞期和囊胚期克隆胚胎的全基因组 DNA 甲基化图谱，并将其与相应阶段的 IVF 胚胎进行比较。我们发现，与 IVF 胚胎相比，克隆胚胎在不同基因组成分的差异甲基化区域分布、CpG 岛分布和甲基化状态、基因本体论特征和整个发育阶段受影响的途径方面表现出明显不同的 DNA 甲基化模式。在囊胚期克隆和 IVF 胚胎中，通过五个随机选择的基因区域的亚硫酸氢盐测序 PCR 对 MeDIP-Seq 产生的数据进行了验证。
