Salamanders are unparalleled among tetrapods in their ability to regenerate many structures, including entire limbs, and the study of this ability may provide insights into human regenerative therapies. The complex structure of the limb poses challenges to the investigation of the cellular and molecular basis of its regeneration. Using CRISPR/Cas, we genetically labelled unique cell lineages within the developing axolotl embryo and tracked the frequency of each lineage within amputated and fully regenerated limbs. This allowed us, for the first time, to assess the contributions of multiple low frequency cell lineages to the regenerating limb at once. Our comparisons reveal that regenerated limbs are high fidelity replicas of the originals even after repeated amputations.

tetra在四足动物的再生许多结构（包括整个肢体）的能力方面是无与伦比的，对这种能力的研究可能会为人类的再生疗法提供见识。肢体的复杂结构对研究其再生的细胞和分子基础提出了挑战。使用CRISPR / Cas，我们对正在发育的a胚胎内的独特细胞谱系进行了遗传标记，并跟踪了截肢和完全再生的肢体内每个谱系的频率。 这使我们第一次能够一次评估多个低频细胞谱系对再生肢体的贡献。我们的比较表明，即使经过多次截肢，再生的肢体仍是原始肢体的高保真复制品。