Placeholder Image

字幕列表 影片播放

  • Unbelievable as it seems

  • we can transfer heredity through the substance of DNA.

  • It's possible for a lot of people to become successful.

  • You have to have the right genes.

  • For the first time, scientists have successfully repaired a faulty gene in human embryos.

  • They used a process known as gene editing.

  • It could help eliminate deadly genetic diseases but some say it's too much like playing God

  • and opening a dangerous Pandora's Box.

  • If this was going to be your baby would you have gone ahead with this?

  • This story begins in the 1850s in a small monastery.

  • And with this monk, Gregor Mendel.

  • While he's experimenting with pea plants, he identifies that traits like color and height

  • pass from one generation to the next.

  • He's the first to establish the principle of inheritance.

  • After Mendel dies the other monks in the abbey take the notes of his astonishing discovery,

  • put them into a pile, and burn them.

  • Well there's no question that Mendel was ahead of his time.

  • I guess you'd say the scientific community was not ready to hear what he was saying.

  • It's fraught with anxiety because there's this idea that you may be playing God

  • you may be trying to determine the future and taking control of things that people should

  • not have control over.

  • So other scientists rediscover what Mendel already knew and in 1905 the word 'genetics'

  • appears for the first time.

  • Research on DNA is one of the great new challenges in science.

  • Skip forward to 1953 and scientists at Cambridge University

  • discover that DNA has a double helix structure.

  • DNA is a code.

  • The structure of DNA showed exactly how that code was put together.

  • Once you knew what the structure was, you could begin to introduce other chemicals

  • you could take things apart, you could put them back together.

  • All those types of things you could suddenly start studying.

  • In the 1970s American biochemist Paul Berg isolates DNA from different sources

  • then he cuts and splices them together.

  • The result is recombinant DNA.

  • He writes a letter about the

  • "potential biohazards" of what he's just discovered.

  • All gene editing experiments stop until 1975

  • and the Asilomar Conference in California.

  • A group of around 140 scientists, physicians and lawyers

  • come up with practical and ethical guidelines.

  • It was almost like a nuclear treaty for biotechnology.

  • Scientists were looking at recombinant DNA with the idea of doing positive things.

  • Somebody else could take these and start using them

  • to make poisons to make bioterrorist weapons.

  • So they felt like the time it was time to take a step back, create some rules

  • and that's what they did.

  • By 1994 the first genetically engineered food hits the shelves.

  • Controversy is swirling around an updated variety of the humble tomato.

  • It's called the Flavr Savr.

  • 2012 is the year of a landmark discovery.

  • It's called CRISPR

  • CRISPR

  • CRISPR Cas9

  • There's a dispute about who actually discovered this tool for editing the human genome.

  • But now scientists can cut out faulty sections of DNA and replace them with healthy ones.

  • It's cheap, it's easy to use.

  • I've watched people use CRISPR in a neighborhood laboratory

  • and these were folks that were no more scientists than you and I.

  • That that's exciting because that gives you all kinds of power to do experimentation.

  • The concerns are that people might use this say to increase the strength of their offspring

  • or to choose eye color, to try to affect personality.

  • The number of gene editing advances using CRISPR is growing worldwide

  • and soon China steps up its efforts to dominate the biotechnology sphere.

  • And in 2018 this happens.

  • Irresponsible, disturbing, inappropriate, that's how two of the inventors of a

  • gene editing tool are describing a Chinese scientist's experiment

  • that helped create genetically edited babies.

  • From what I've read he had relatively high-minded ideals about what he was doing and I think

  • his impression was that it was going to be welcomed.

  • The audience that he sat in front of was really pretty horrified and eventually

  • the Chinese government really started to turn against him.

  • The interesting thing is that every time a new technology comes along everybody talks

  • about it as though it's a Pandora's Box

  • and that these evils are going to fly out with a good.

  • And that is true.

  • There's always risk but that's the story of science.

  • The whole idea is to open up these boxes and to see what's inside.

  • And each time you open up a box, there's another box inside of it.

  • And that's going, what's going to happen with CRISPR is the revelations will continue and

  • the controversies will continue.

  • That's just the way science goes.

Unbelievable as it seems

字幕與單字

單字即點即查 點擊單字可以查詢單字解釋

B1 中級

基因編輯簡史 (A Brief History of Gene Editing)

  • 3 0
    林宜悉 發佈於 2021 年 01 月 14 日
影片單字