Analysis of difference between female and male genome determined in pronuclear stage embryo.

在哺乳动物中，母系和父系基因组的基本功能是不同的。我们发现外源DNA注射到雌性或雄性原核后，其甲基化状态受到不同的控制。当外源DNA采用H19印迹控制区时，雄性原核注射组的甲基化水平高于雌性原核注射组。这一结果表明，胚胎中母体和父本特异性表观遗传标记可能参与了受精后印迹基因亲本特异性甲基化的建立和维持。

In mammals, a fundamental function differs between maternaland paternal genomes. We found that exogenous DNA was controlled differently in its methylation status after injection into the female or male pronucleus. When H19 imprinting control region was used for exogenous DNA, its methylation level was higher in male pronucleus injection than that by female pronuleus injection. This result suggests that maternal and paternal specific epigeneteic marks in embryos may contribute in the establishment and maintenance of parental origin specific methylation of imprinting genesafter fertilization.