中文摘要：

由使用免疫荧光对 5-methylcytosine (5MeC ) 与抗体染色的途径，现在的学习检测了克隆的羊似的胚胎的 DNA 甲基化模式。从在 vitro 授精导出的胚胎也为参考目的被检验。结果显示出那：(1 ) 在培植前发展期间，克隆的胚胎显示了类似的脱甲基作用侧面到使肥沃的胚胎；也就是说，甲基化水平减少了到在 8 房间舞台最低，然后在 morulae 舞台再增加了。然而，甲基化水平比在匹配阶段的使肥沃的胚胎在克隆的胚胎显然是更高的，特别在 8 房间舞台并且以后；(2 ) 在胚囊上演，在克隆的胚胎的甲基化模式在使肥沃的胚胎与那不同。在克隆的胚囊，，内部房间质量(ICM ) 在 in-vitro 展出了可比较的水平到 trophectoderm 房间(TE ) 使肥沃的胚囊甲基化水平 ICM 比 TE 的低，它不与那由另外的作者报导了一致。这些结果显示那 DNA 甲基化，暗示异常 DNA 甲基化 reprogramming 可以是引起的因素之一是反常地，在克隆的胚胎的 reprogrammed 克隆胚胎发展失败。

英文摘要：

By using the approach of immunofluorescence staining with an antibody against 5-methylcytosine （5MeC）, the present study detected the DNA methylation patterns of cloned ovine embryos. The embryos derived from in vitro fertilization were also examined for reference purpose. The results showed that： （1） during the preimplantation development, cloned embryos displayed a similar demethylation profile to the fertilized embryos; that is, the methylation level decreased to the lowest at 8-cell stage, and then increased again at morulae stage. However, methylation level was obviously higher in cloned embryos than in stage-matched fertilized embryos, especially at 8-cell stage and afterwards; （2） at blastocyst stage, the methylation pattern in cloned embryos was different from that in fertilized embryos. In cloned blastocyst, inner cell mass （ICM） exhibited a comparable level to trophectoderm cells （TE）, while in in-vitro fertilized blastocyst the methylation level of ICM was lower than that of TE, which is not consistent with that reported by other authors. These results indicate that DNA methylation is abnormally reprogrammed in cloned embryos, implying that aberrant DNA methylation reprogramming may be one of the factors causing cloned embryos developmental failure.