The chromodomain helicase DNA binding domain 2 (CHD2) gene is an ATPase and a member of the SNF2-like family of helicase-related enzymes. CHD2 plays critical roles in human brain development and function, and homozygous mutation of Chd2 in mice results in perinatal lethality. To further elucidate the effects of chd2, we used CRISPR/Cas9 to create two chd2-knockout strains (fdu901, 11,979-11982delGGGT, and fdu902, 27350delG) in zebrafish. We found that the deformity and mortality rates of fdu901 and fdu902 were higher than those of the wild type. Developmental delay was more obvious and embryo mortality was higher in fdu901 than in fdu902. However, the embryo deformity rate in fdu902 was higher than that in fdu901. Although there were no significant differences in behavior between the two knockout zebrafish and wild-type zebrafish at 7 days post fertilization (dpf), fdu901 and fdu902 zebrafish showed different alterations. The excitability of fdu902 was higher than that of fdu901. Overall, our data demonstrate that two homozygous chd2 knockout mutations were survivable and could be stably inherited and that fdu901 and fdu902 zebrafish differed in behavior and morphology. These two models might be good tools for understanding the functions of the different domains of chd2.

Keywords: chd2; Behavior; Knockout; Morphology; Zebrafish.

© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.

染色体结构域解旋酶DNA结合域2（CHD2）基因是一种ATP酶，属于SNF2样家族的解旋酶相关酶。CHD2在人类大脑发育和功能中起着关键作用，并且小鼠中的Chd2同合子突变会导致围产期致死性。为了进一步阐明chd2的影响，我们使用CRISPR/Cas9技术在斑马鱼中创建了两个chd2敲除品系（fdu901, 11979-11982delGGGT和fdu902, 27350delG）。我们发现，fdu901和fdu902的畸形率和死亡率均高于野生型。fdu901中的发育延迟更加明显且胚胎死亡率更高，而fdu902中的胚胎畸形率则高于fdu901。然而，在受精后7天（dpf）时，两种敲除斑马鱼与野生型斑马鱼之间在行为上没有显著差异，但fdu901和fdu902斑马鱼表现出不同的变化。fdu902的兴奋性高于fdu901。总的来说，我们的数据显示两个同合子chd2敲除突变是可存活并可以稳定遗传的，并且fdu901和fdu902斑马鱼在行为和形态上存在差异。这两种模型可能是理解不同域的chd2功能的良好工具。

关键词： chd2；行为；敲除；形态；斑马鱼。

© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.