Using gene editing technology to impart characteristics of other species to humans, especially the ability of fish to breathe underwater, is an extremely complex and unsolved scientific challenge. At present, gene editing technologies (such as CRISPR-Cas9) are mainly used to repair gene defects and study gene functions, rather than to impart completely new physiological characteristics. ### Theoretical challenges and steps: 1. **Identification of key genes**: First, it is necessary to clarify the key biological mechanisms of fish breathing underwater, such as the function of gills and their implementation at the molecular and genetic levels. The genes that control these functions need to be identified and isolated. 2. **Assessing feasibility**: Even if the relevant genes are identified, transferring their functions to human biological systems still involves huge complexity. The gills of fish have fundamental physiological differences from human lungs, and simple gene transfer may not achieve the same function. 3. **Gene editing and expression**: Assuming that the relevant genes are found, they can be edited using tools such as CRISPR, but the problem of how foreign genes can be correctly expressed and function in new biological environments needs to be solved. 4. **Biological adaptability and ethical considerations**: Even if gene editing technology achieves stable integration of foreign genes, the biological adaptability and long-term biological effects of this new characteristic in the human body need to be solved. In addition, the ethical issues of modifying the human genome also need to be carefully considered. 5. **Safety and health assessment**: Any new gene editing application must undergo extensive safety and health assessments to ensure that there will be no negative impacts on individual health or the next generation. 6. **Regulation and social acceptance**: Even if it is technically feasible, it still needs to pass strict regulatory review and gain social acceptance. ### Current research progress: At present, gene editing technology is mainly used in the fields of disease treatment and research, such as repairing genetic diseases or studying gene function. The issue of giving humans the characteristics of other species of animals is still in the theoretical and science fiction stage, and there is no substantial research to prove its feasibility. ### Conclusion: Even if it is theoretically possible, giving humans the abilities of other species involves major technical, ethical and social challenges. Current scientific efforts are mainly focused on saving and improving health, rather than subversively changing human abilities. Future technological advances may be able to realize such a vision to a certain extent, but at this stage, it is still a distant dream.