Researchers have used advanced base-editing technology to show that the NANOG gene is essential for starting the human embryonic development process.

研究人員利用先進的鹼基編輯技術，證明了 NANOG 基因對於啟動人類胚胎發育過程至關重要。

The study, led by Kathy Niakan from the University of Cambridge, used a technique called adenine base editing (ABE8e) to disable the NANOG gene in human embryos. This method was chosen because it changes single DNA units, which reduces the risk of genetic damage and chromosomal errors often caused by traditional CRISPR-Cas9 methods. The results show that when NANOG is inactive, the pluripotent epiblast—the group of cells that forms the human body—cannot develop. However, the cells that form the placenta and yolk sac continue to grow normally.

這項研究由劍橋大學的 Kathy Niakan 領導，使用了一種稱為腺嘌呤鹼基編輯 (ABE8e) 的技術來禁用人類胚胎中的 NANOG 基因。選擇此方法是因為它能改變單一的 DNA 單位，從而降低傳統 CRISPR-Cas9 方法經常引起的基因損壞和染色體錯誤風險。結果顯示，當 NANOG 失去活性時，形成人體的多能原胚層 (pluripotent epiblast) 無法發育。然而，形成胎盤和卵黃囊的細胞仍能正常生長。

This discovery reveals a major difference between human and mouse embryos. In mice, the absence of NANOG prevents the yolk sac from forming, whereas human embryos can still develop this structure. Consequently, the study emphasizes that direct research on human embryos is necessary to truly understand how they develop. From a medical perspective, using NANOG as a marker for viability could improve the success rates of in vitro fertilization (IVF), as current methods rely on visual appearance, which often fails to predict if an embryo will successfully implant.

此發現揭示了人類與小鼠胚胎之間的一個重大差異。在小鼠中，缺乏 NANOG 會導致卵黃囊無法形成，而人類胚胎仍能發育出此構造。因此，研究強調必須直接對人類胚胎進行研究，才能真正理解其發育過程。從醫學角度來看，將 NANOG 作為生存能力的標記可提高體外受精 (IVF) 的成功率，因為目前的方法依賴視覺外觀，往往無法準確預測胚胎是否能成功著床。

Despite the precision of this editing tool, the researchers encountered a significant technical problem known as mosaicism. This means that many edited embryos had a mixture of both modified and unmodified cells. Because of this inconsistency, the technology is not yet suitable for treating inherited genetic disorders in humans. Furthermore, while the method is safer for altering genes, the scientific community agrees that the technology is not yet mature enough to create gene-edited human babies.

儘管該編輯工具具有高精確度，但研究人員遇到了被稱為「嵌合現象」(mosaicism) 的重大技術問題。這意味著許多經編輯的胚胎中混合了修改後與未修改的細胞。由於這種不一致性，該技術目前尚不適用於治療人類的遺傳性基因疾病。此外，雖然該方法在改變基因方面較為安全，但科學界一致認為，該技術尚未成熟到足以創造基因編輯過的人類嬰兒。

The study confirms that NANOG is essential for human development and shows that base editing is a useful tool, although the problem of mosaicism still needs to be solved.

研究確認了 NANOG 對人類發育至關重要，並證明了鹼基編輯是一個有用的工具，儘管嵌合現象的問題仍需解決。