引爭議！大陸在胚胎進行人類基因編輯實驗 2015年04月24日 14:09 林淑燕／綜合報導 科學家對於人類基因修改有著強烈的好奇，過去已經有在成年人細胞、動物胚胎上進行研究，但從來沒有人在人類胚胎上進行實驗。大陸中山大學生物學團隊最近在一份英文學術期刊上發表論文，發表被認為是全球首次在胚胎上進行基因修改實驗。這項引發倫理爭議的創舉已經引起國際高度關注，科學家紛紛提出反對並呼籲全球應終止這類型在人類胚胎上進行研究的實驗。根據BBC中文網站報導，大陸中山大學生物學副教授黃軍就和他的團隊，最近完成一次在人類胚胎進行基因修改的實驗，這份報告並且發表在由大陸機構主辦的英文學術月刊「Protein & Cell」（蛋白與細胞）上。該項研究是從生殖診所裡取得86個無法發育成嬰兒的問題胚胎，對與地中海貧血症有關的基因細胞進行被稱為「CRISPR/Cas9」的基因編輯實驗，結果有28個胚胎的基因被成功修改。雖有成功修改的紀錄，但是黃君就說這項技術其實還不成熟，並且已經停止這項實驗。《自然》（Nature）雜誌報導美國哈佛醫學院生物學家喬治·達利博士（Dr George Daley）的說法，「這樣的研究是一個里程碑，但同樣令人警惕。」達利博士說，「他們（中國科學家）的研究應該是一個嚴重的警告，任何實驗者都不應該認為這項技術已經凖備好可以進行消除疾病基因的測試。」黃軍就和他的團隊的研究報告曾因倫理爭議而被《自然》和《科學》（Science）雜誌拒絕投稿。BBC報導，這項報告發表後，國際再生醫學聯盟組織（The Alliance for Regenerative Medicine）再度提出呼籲，希望中止相關研究。法新社也報導，國際再生醫學聯盟組織認為，基於修改人類再生細胞DNA所存在的重大安全和道德問題，這項研究仍然非常不成熟；在現在進行這方面的研究「令人不能接受」。
China transmuted human embryos through CRISPR/Cas9 Robert Nicholls The majority of scientists from around the world called for a halt studies involving genetic codification on human embryos. This appeal becomes stronger when the Chinese team successfully manipulates human embryos. Research by the Chinese team led by Junjiu Huang, a researcher gene of Sun Yat-sen University. The Chinese researchers have explained that the process used for the modification of embryos derived from a fertility clinic. Embryos were collected and nonviable embryos that are not likely to live because they have the advantage of chromosomes. Chinese researchers are trying to modify the genes responsible for blood disorder called beta thalassemia. The said study was led by Sun Yat-sen University's gene function researcher Junjiu Huang, who was ably supported a group of Chinese scientists. The researchers have explained the process adopted by them for editing genomes of human embryos acquired from a fertility clinic. The collected embryos were nonviable and their chances of resulting in live birth were zero as they carried an additional set of chromosomes because of being fertilized by a couple of sperms. The Chinese researchers tried to modify a gene that according to them was responsible for beta- thalassemia; for those who don't know: thalassemia is an inherited recessive blood disorder marked by abnormal hemoglobin formation. They carried out the modification using a gene-editing technique called CRISPR/Cas9. As many as 86 embryos were injected by the researchers; following this, they waited for 48 hours to allow the molecules replacing the missing DNA to begin its operations. Out of the 86 embryos, 71 managed to survive; tests were carried out on 54 of them. During the tests, researchers found that just 28 got spliced successfully; they also discovered that just a tiny fraction of those possessed the substituted genetic material. According to Huang, for carrying out the process on normal embryos, being close to 100% is an absolute necessity. He added that failure of achieving that 100% is the only reason why they have decided to stop the study for now. Huang and his team feels that the technique adopted by them is still not mature enough for being tested on human embryos. What was more concerning was the surprisingly high number of unintentional mutations taking place during the process. The rate was significantly higher than those seen in any other gene-editing experiment carried out previously; these include both studies carried out on mice cells and studies conducted on cells of adult humans.
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