CRISPR: What is the future of gene editing? | Start Here

Summary

CRISPR-Cas9, a revolutionary gene-editing technology, offers unprecedented potential to combat genetic diseases like muscular dystrophy and cancer. Discovered by Emmanuelle Charpentier and Jennifer Doudna, it functions as 'genetic scissors' by targeting and replacing faulty genes with healthy ones. However, ethical concerns arise with germ-line editing, as seen in the controversial case of the world's first CRISPR-modified babies by He Jiankui, which sparked international outrage and calls for stricter regulations. While 75 countries ban its use in reproduction, the technology's potential to transform lives remains immense, despite the risks and unknowns.

Takeaways

• 🔬 CRISPR is a revolutionary gene-editing technology that has been around for less than a decade and has already been recognized with a Nobel Prize in 2020.
• 🧬 Genes are the body's blueprint, made up of DNA that instructs cells to make proteins, which in turn determine our physical traits and functions.
• 🛠️ CRISPR-Cas9 acts as a pair of 'genetic scissors', allowing scientists to cut out faulty genes and potentially replace them with healthy ones.
• 🌟 The discovery of CRISPR was accidental, stemming from research into how bacteria use CRISPR to store and utilize pieces of viral DNA for defense.
• 💉 CRISPR has been used in medical treatments, such as for sickle cell disease, with one patient, Victoria Gray, experiencing significant symptom reduction.
• 🚫 The use of CRISPR on germ-line cells, which can affect future generations, is controversial and largely prohibited due to ethical and safety concerns.
• 👶 The birth of the world's first CRISPR-modified babies by Chinese scientist He Jiankui in 2018 sparked international outrage and raised questions about consent and the unknown long-term effects.
• 🏢 He Jiankui faced legal consequences for his unauthorized experiments, receiving a three-year prison sentence and a lifetime ban from reproductive medicine.
• 🌱 Despite the controversy, CRISPR research continues in other areas, such as plants and animals, indicating its broad potential applications.
• 📋 There is a push for more regulation and guidelines regarding the use of CRISPR to ensure ethical practices and prevent misuse.
• 🌐 The script highlights the dual nature of CRISPR's potential, emphasizing both its capacity to transform lives positively and the risks associated with its misuse.

Q & A

What is CRISPR and how does it relate to gene editing?

CRISPR, which stands for Clustered Regularly Interspaced Short Palindromic Repeats, is a revolutionary gene-editing technology that allows scientists to perform precise changes to the DNA within living organisms. It functions as a pair of genetic scissors, enabling the targeting and editing of specific genes.

Who were the scientists awarded the Nobel Prize for the development of CRISPR?

Emmanuelle Charpentier and Jennifer Doudna were awarded the Nobel Prize in Chemistry in 2020 for their work on the CRISPR-Cas9 genetic scissors.

How does CRISPR-Cas9 work in the context of bacteria?

In bacteria, CRISPR-Cas9 works as a defense mechanism against viruses. It stores snippets of viral DNA, and when the virus returns, the CRISPR DNA is replicated. Parts of this replication join with the Cas9 protein to locate and cut the viral DNA, thereby neutralizing the threat.

What is the potential application of CRISPR in treating diseases?

CRISPR has the potential to treat, and possibly cure, genetic diseases such as muscular dystrophy, cystic fibrosis, and certain types of cancer by editing faulty genes and replacing them with healthy ones.

Can you explain the case of Victoria Gray and how CRISPR was used to treat her?

Victoria Gray was the first person in the US to receive a CRISPR-based treatment for sickle cell disease. Doctors infused her with over 2 billion of her own genetically edited bone marrow cells, which helped to alleviate her symptoms significantly.

What is the difference between editing somatic cells and germ-line cells in the context of CRISPR?

Somatic cells are all the cells in the body except for sperm and egg cells. Genetic changes made in somatic cells are not passed on to offspring. In contrast, germ-line cells are sperm, egg, or fertilized eggs, and changes to these cells can be inherited by future generations.

Why was the use of CRISPR by He Jiankui controversial?

He Jiankui's use of CRISPR was controversial because he edited germ-line cells to create the world's first CRISPR-modified babies, which raised ethical concerns about consent, the potential for unintended genetic mutations, and the societal implications of designer babies.

What are the current regulations regarding the use of CRISPR in human reproduction?

Seventy-five countries have prohibited the use of CRISPR in human reproduction. There is an ongoing effort by scientists and governments to establish more comprehensive regulations and guidelines to govern the use of this technology.

What was the outcome for He Jiankui after his controversial use of CRISPR?

He Jiankui was sentenced to three years in prison and was banned from working on reproductive medicine for life due to his unauthorized and ethically questionable use of CRISPR technology on human embryos.

How is CRISPR being used in non-human applications?

CRISPR is being experimented with in plants and animals for various purposes, such as improving crop yields, enhancing disease resistance, and studying animal genetics, without the ethical concerns associated with human germ-line editing.

What are the potential risks of using CRISPR technology?

The potential risks of using CRISPR include unintended genetic mutations with unpredictable side effects, the ethical issue of consent (especially in the case of embryos), and the broader societal implications of altering the human gene pool.

Outlines

00:00

🧬 CRISPR: Revolutionizing Gene Editing

The script introduces CRISPR, a groundbreaking gene-editing technology that has been acknowledged with a Nobel Prize. It discusses the potential of CRISPR to combat diseases and enhance crops, while also touching on ethical concerns and fears. The summary explains how CRISPR-Cas9 functions as 'genetic scissors,' enabling scientists to edit faulty genes, with an example of its application in treating sickle cell disease. The segment also raises questions about the extent to which gene editing should be applied, especially concerning germ-line editing and the controversial case of the world's first CRISPR-modified babies.

05:05

🚫 Ethical and Regulatory Challenges of CRISPR

This paragraph delves into the ethical implications and regulatory responses to CRISPR technology. It highlights the permanent and hereditary nature of germ-line cell editing, the unpredictable side effects of genome mutations, and issues of consent, especially in the case of the CRISPR-modified babies born to HIV-resistant parents without their consent. The summary outlines the international efforts to draft guidelines for CRISPR use and mentions the legal consequences faced by the Chinese scientist He Jiankui. It concludes with a reflection on the dual nature of CRISPR's potential to improve lives while also posing significant risks if misused.

Keywords

💡Gene editing

Gene editing refers to the process of altering an organism's DNA. In the context of the video, it is the core theme that discusses the potential of CRISPR technology to modify genes, which can lead to curing diseases and improving crops. The script highlights the revolutionary aspect of gene editing and its ethical implications.

💡CRISPR

CRISPR, derived from 'Clustered Regularly Interspaced Short Palindromic Repeats', is a gene-editing tool that has gained significant attention for its ability to perform precise cuts in DNA sequences. The video emphasizes CRISPR's role in potentially fighting diseases and the ethical debate surrounding its use in human gene pools.

💡Nobel Prize

The Nobel Prize is an international award given to those who make outstanding contributions in various fields. In the script, it is mentioned to honor the inventors of CRISPR technology, Emmanuelle Charpentier and Jennifer Doudna, for their groundbreaking work in genetic engineering.

💡DNA

DNA, or deoxyribonucleic acid, is the hereditary material in humans and almost all other organisms. The script explains that genes, which are made up of DNA, carry the instructions for making proteins that determine our body's functions and appearance. DNA is central to the discussion of gene editing.

💡Proteins

Proteins are large molecules that play a crucial role in the body's functions. As mentioned in the script, DNA instructs cells on how to make proteins, which in turn carry out the body's functions. The video connects the role of proteins to the process of gene editing.

💡Genetic diseases

Genetic diseases are illnesses caused by changes or mutations in an individual's DNA. The script discusses how gene editing, specifically with CRISPR, could potentially treat or even cure genetic diseases such as muscular dystrophy, cystic fibrosis, and cancer.

💡Somatic cells

Somatic cells are all the body's cells except for sperm and egg cells. The video explains that scientists are currently using CRISPR to edit somatic cells to treat diseases without affecting the human gene pool, emphasizing the importance of consent and the non-heritable nature of these changes.

💡Germ-line cells

Germ-line cells are sperm and egg cells, which pass genetic information to the next generation. The script describes the controversial case of He Jiankui, who edited germ-line cells to create the world's first CRISPR-modified babies, raising ethical concerns about permanent genetic changes and lack of consent.

💡Designer babies

Designer babies refer to the concept of genetically modifying human embryos to select for certain traits. The video raises the ethical concerns of this idea, suggesting that misuse of CRISPR technology could lead to attempts at creating 'designer babies,' with unknown and potentially harmful consequences.

💡Regulation

Regulation in the context of the video pertains to the establishment of rules and guidelines to govern the use of gene-editing technologies like CRISPR. The script mentions that many countries have prohibited its use in human reproduction, and an international commission is working on drafting guidelines to ensure ethical use.

💡CRISPR-Cas9

CRISPR-Cas9 is the specific tool used for gene editing, named after the CRISPR system and the Cas9 protein that it uses to cut DNA. The video describes how this tool works as a pair of 'genetic scissors,' and how it was discovered by studying bacteria's defense mechanisms against viruses.

Highlights

CRISPR is a revolutionary gene editing technology less than 10 years old that can perform surgery on genes.

CRISPR inventors Emmanuelle Charpentier and Jennifer Doudna won the Nobel Prize in 2020.

CRISPR can potentially fight diseases and improve crops.

Genes are the blueprint for making everything the body needs, with over 20,000 in humans.

Some gene variations can cause sickness, but CRISPR may enable scientists to change those genes.

CRISPR-Cas9 acts as a pair of genetic scissors, allowing targeted gene editing.

Charpentier and Doudna discovered CRISPR by studying how bacteria protect themselves from viruses.

CRISPR is simple to use, cheap, and has the potential to treat or cure genetic diseases like muscular dystrophy, cystic fibrosis, and cancer.

Victoria Gray was the first person in the US to receive a CRISPR-based treatment for sickle cell disease, with significant symptom improvement.

CRISPR used in this way is not hereditary and does not affect the human gene pool.

Some suggest using CRISPR on early embryos for genetic fixes, but many scientists consider this a step too far due to safety and societal concerns.

Chinese scientist He Jiankui caused outrage by creating the world's first CRISPR-modified babies, altering their germ-line cells.

He Jiankui was sentenced to three years in prison and banned from reproductive medicine for life.

The potential misuse of CRISPR raises concerns about creating designer babies and permanently altering the human gene pool.

Seventy-five countries prohibit the use of CRISPR in human reproduction, but more regulations are needed.

An international commission is drafting guidelines to regulate the use of CRISPR.

CRISPR research continues in plants and animals, despite the controversy surrounding its use in humans.

The full potential of CRISPR to transform lives without harming others is a power that people are unlikely to ignore.

Transcripts

Let’s talk about gene editing and its potential to change lives.

It’s because of CRISPR — a technology that’s not even 10

years old and can basically perform surgery on our genes.

The inventors got a Nobel Prize for it in 2020.

CRISPR fans say it’ll fight diseases and improve crops.

Other people? Well, Hollywood tapped into their fears a long time ago.

At least one scientist has crossed the line.

So how does gene editing actually work?

Can CRISPR be used to cure disease?

And how far should we be allowed to go in transforming the human race?

Genes are the blueprint for making everything the body needs.

And human beings have more than 20,000 of them.

Genes are made up of DNA and that instructs the cell how to make a protein.

Those proteins carry out the functions of the body and determine the way we look.

But some gene variations can make us sick.

Scientists, though, may now have the unprecedented power to change those genes.

It’s all because of the work done by two Nobel Prize winning scientists:

Emmanuelle Charpentier and Jennifer Doudna.

What they discovered has unleashed a whole new era of genetic engineering

that’s advancing just about every day.

The tool is called CRISPR–Cas9.

And like so often happens in science they discovered it by chance.

Charpentier and Doudna were studying how bacteria protect themselves from viruses

because, yes, bacteria get sick too.

They found that bacteria have a part of their DNA called CRISPR

that stores tiny pieces of a virus’s DNA.

A copy of that bacterial CRISPR DNA is made the next time the virus comes back.

Small parts of the copy then join up with a protein called Cas9.

So CRISPR–Cas9 goes looking for that matching bit of DNA

in the virus, latches onto it and through a chemical reaction

it snips the viral DNA to destroy it.

It’s why scientists describe CRISPR–Cas9 as a pair of genetic scissors.

So Charpentier and Doudna then thought:

Why can’t we harness that same natural process

but programme it to cut out genes that are faulty

and replace them with healthy ones.

That was the lightbulb moment.

It’s simple to use and cheap and that makes it revolutionary.

Because it could treat, perhaps even cure, genetic diseases

like muscular dystrophy, cystic fibrosis, even cancer.

And a lot of attention has been on sickle cell disease.

In fact scientists have already used it on a woman named Victoria Gray.

She was the first person in the US to receive a CRISPR-based treatment for the disease.

Doctors infused her with more than 2 billion of her own genetically edited bone marrow cells.

More than a year later almost all her symptoms are gone.

Just to be clear — CRISPR is being used here like any other medical treatment.

Any genetic changes stay with that patient. They aren’t passed on to their children.

They’re not hereditary changes that affect the human gene pool forever.

That’s because scientists are fixing faulty genes in somatic cells — basically all the cells in

our bodies except the single-cell sperm and egg.

And it’s important to point out the patient is an adult who’s consented to the treatment.

But some are suggesting using CRISPR on early embryos to make the genetic fix.

And for a lot of safety and societal reasons scientists say that’s a step too far.

But that didn’t stop a Chinese scientist from going there.

In 2018 He Jiankui announced the birth of the world’s first CRISPR-modified babies —

twin girls known only as Lulu and Nana.

There was outrage.

He’d altered a gene to try to protect them from HIV because their father has AIDS.

But he did it while the girls were still in a petri dish.

And that’s why his use of CRISPR technology is a problem.

He genetically altered what are called germ-line cells:

the sperm, the egg, or in the case of the twin girls, a fertilised egg at the single-cell stage.

Changes to DNA here appear in every cell in a person’s body.

You might say that’s an efficient fix

but those genetic changes are permanent and are passed onto future generations.

Plus, this is unchartered territory.

Scientists say there’s a very real risk that an edit could cause a mutation in the genome with side effects that we just can’t predict.

There’s also the issue of consent.

The girls obviously had no say in the changes made to their bodies.

That experiment alone raised the spectre of designer babies, making people smarter, stronger, maybe more attractive.

So what’s being done to regulate it?

Seventy-five countries already prohibit the use of CRISPR in human reproduction.

But many scientists and governments agree more rules are needed.

Right now we have an international commission that’s started to draft some guidelines.

None of that, though, has stopped scientists from experimenting with CRISPR —

in plants and animals at least.

So what happened to the man who did interfere?

Well, He Jiankui was sentenced to three years in prison and banned from working on reproductive medicine for life.

And the twin girls? No one really knows where they are or whether they’re healthy.

We don’t even know who else in the world is trying this technology.

There’s a good chance someone will misuse it and potentially change the human race.

That’s enough to want to bury this technology.

But CRISPR has enormous potential to transform some people’s lives without hurting anyone else.

That’s a power people just won’t want to ignore.

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