什么是CRISPR ?它為什么有爭議?
Two women have won the Nobel prize in chemistry for the development of a revolutionary gene editing tool that's been described as "rewriting the code of life."
兩位女性因開發(fā)出一種革命性的基因編輯工具而獲得諾貝爾化學(xué)獎,該工具被稱為“改寫生命密碼”的工具。
The technique discovered by Emmanuelle Charpentier, the director at the Max Planck Institute for Infection Biology, and Jennifer A. Doudna, a biochemist at the University of California Berkeley, is known as CRISPR/Cas9.
這項技術(shù)是由馬克斯·普朗克感染生物學(xué)研究所所長艾曼紐·莎彭蒂耶和加州大學(xué)伯克利分校的生物化學(xué)家詹妮弗·A·杜德納發(fā)現(xiàn)的,被稱為CRISPR/Cas9。
What is CRISPR (pronounced "crisper") and why has it been controversial?
什么是CRISPR(發(fā)音為“crisper”)?為什么它一直備受爭議?
How it works
它是如何起作用的
DNA is like the instruction manual for life on our planet, and CRISPR/Cas9 can target sites in genetic material.
DNA就像我們星球上生命的指導(dǎo)手冊,CRISPR/Cas9可以在遺傳物質(zhì)中靶向定位。
This allows scientists to change it by knocking out a particular gene or inserting new genetic material at a predetermined site in our DNA.
這使得科學(xué)家可以通過敲除一個特定的基因或在我們DNA的預(yù)定位置插入新的遺傳物質(zhì)來改變它。
Cas9, a type of modified protein, acts like a pair of scissors that can snip parts of DNA strands.
Cas9是一種修飾蛋白,其作用就像一把剪刀,可以剪斷部分DNA鏈。
"Doudna and Charpentier showed that CRISPR works like a pair of scissors that can be targeted to cut specific DNA sequences, said Andrew Holland, an assistant professor in the Department of Molecular Biology and Genetics at Johns Hopkins School of Medicine. "After cutting, the repair of the DNA code enables it to be altered. This has allowed scientists to change the DNA code in a targeted way to help understand and treat genetic disease," he told CNN via email.
杜德納和夏彭蒂耶的研究表明,CRISPR的工作原理就像一把剪刀,可以靶向切斷特定的DNA序列,約翰·霍普金斯醫(yī)學(xué)院分子生物學(xué)和遺傳學(xué)系助理教授安德魯·霍蘭德說。“在切割后,DNA密碼的修復(fù)使它能夠被改變。這使得科學(xué)家有針對性的改變DNA密碼,以幫助理解和治療遺傳疾病,”他通過電子郵件告訴CNN。
The technology has worked in pretty much every organism that it has been used on, including plants, microbes and humans.
這項技術(shù)適用于幾乎所有的生物,包括植物、微生物和人類。
"What the system does is that it can recognize (a) certain specific gene in the genome of ourselves and correct mutations, do some copy pasting, do some editing like we edit a text. The system can edit the genome and change the properties of the genes," Charpentier said in 2016 when she was interviewed by CNN.
“這個系統(tǒng)所做的是,它能識別我們基因組中的某個特定基因并糾正突變,做一些復(fù)制粘貼,像編輯文本一樣進行編輯。這個系統(tǒng)可以編輯基因組并改變基因的屬性,”2016年,當(dāng)她接受CNN采訪時,她說。
How is it used?
它是如何使用的?
It is already having a major impact on biomedical research, clinical medicine and agriculture. For example, it's been used to grow rice that accumulates lower levels of potentially toxic heavy metals and create livestock with more desirable traits.
它已經(jīng)對生物醫(yī)學(xué)研究、臨床醫(yī)學(xué)和農(nóng)業(yè)產(chǎn)生了重大影響。例如,它被用來種植水稻,這種水稻積累的潛在有毒重金屬含量較低,并培育出具有更理想特征的牲畜。
It was used for the first time in humans in 2016 and a trial is underway in the United States to use the experimental technology to treat a dozen patients with sickle cell disease, a group of inherited blood disorders.
該技術(shù)于2016年首次在人類身上使用,美國正在進行一項試驗,利用這項實驗技術(shù)治療12名鐮狀細(xì)胞病患者,鐮狀細(xì)胞病是一組遺傳性血液疾病。
Related technologies may be able to potentially correct up to 89% of genetic defects, scientists have said.
科學(xué)家們說,相關(guān)技術(shù)可能能夠糾正高達(dá)89%的基因缺陷。
Why has it been controversial?
為什么會有爭議?
While it has immense potential to transform our lives, the technology has raised many ethical questions.
盡管這項技術(shù)有改變我們生活的巨大潛力,但它也引發(fā)了許多倫理問題。
Claes Gustafsson, secretary of the Nobel committee in chemistry and a professor of biochemistry and biophysics at Stockholm University, said that with "every really powerful technology, in life sciences or elsewhere, there's a possibility of misuse."
諾貝爾化學(xué)委員會秘書、斯德哥爾摩大學(xué)生物化學(xué)和生物物理學(xué)教授克萊斯·古斯塔夫松說,“在生命科學(xué)或其他領(lǐng)域,每一項真正強大的技術(shù)都有可能被濫用。”
"Everyone has agreed that it cannot be used for germline engineering. You can't make heritable changes to human DNA. That is far too uncertain at this point," added Gustafsson. "There are specific genetic diseases you can think of curing for the individual but not in a heritable way."
“每個人都同意它不能用于種系工程。你不能對人類DNA進行遺傳性的改變。在這一點上,這太不確定了,”古斯塔夫松補充道。“有些特定的遺傳病你可以考慮為個人治療,但不是以遺傳的方式。”
Scientists have called for a moratorium on human germline editing, while efforts are being made to better regulate use of the technology. An international commission said in September it was too early for gene-edited human embryos to be used to create a pregnancy.
科學(xué)家呼吁暫停人類種系編輯,同時也在努力更好地規(guī)范該技術(shù)的使用。一個國際委員會在9月份表示,將基因編輯過的人類胚胎用于受孕還為時過早。