DNA damage quantified as the comet tail length was assessed using in vitro and in vivo comet assay on one- and two-cell mouse embryos obtained by natural mating. The use of a protocol with three layers of agarose reduces the embryo loss and makes it possible to study a small number of embryos. A significantly lower level of basal, but not induced DNA damage was found in embryos with cleaved zona pellucida compared to an embryo with intact zona pellucida. There were no significant differences in the length of the comet's tail between embryos lysed in different lysis solutions, both in cases of basal and induced DNA damage. A significant increase in the comet tail length was detected in one-cell embryos of mice treated with methyl methanesulfonate and etoposide compared to the control. The data show that DNA damage induced in maternal germ cells persists, which can be detected in embryos using the comet assay.

中文翻译：

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单细胞和双细胞小鼠胚胎的彗星试验

使用体外和体内彗星试验对通过自然交配获得的单细胞和双细胞小鼠胚胎进行量化，量化为彗尾长度的 DNA 损伤。使用具有三层琼脂糖的方案可减少胚胎损失并使研究少量胚胎成为可能。与具有完整透明带的胚胎相比，在具有切割透明带的胚胎中发现了显着较低水平的基础 DNA 损伤，但未诱导 DNA 损伤。在不同裂解溶液中裂解的胚胎之间，彗星尾部的长度没有显着差异，无论是在基础 DNA 损伤还是诱导 DNA 损伤的情况下。与对照相比，在用甲基磺酸甲酯和依托泊苷处理的小鼠的单细胞胚胎中检测到彗尾长度显着增加。