Comments

You must log in or register to comment.

exileonmainst t1_j4rdqcu wrote

so how does the edit actually happen? like how do you edit the DNA of all the heart cells (or enough of them) to fix this?

28

LitLitten t1_j4rh2kh wrote

If it’s like other forms, typically through a viral vector. The carrier molecule drops a specific piece of DNA to a gene and overwrite/replacing it with a correct copy.

26

Evianicecubes t1_j4t09mz wrote

I’m too lazy to look it up, is this applied intravenously and changes all cells it encounters, or just injected directly into the target tissue?

1

Luziferatus42 t1_j4ulgyd wrote

Simple answer. It can be made to target specific cell types. But like in nature, there is probability distribution, a small chance for errors is always present.

But again, if the change happens in the wrong cell type, it can perhaps be neglected, because the changed gene sequence is not "used" in this type of cell.

Life is a very complex systems, wich is ultimately build on the sequence of just four molecules. This sequence is the "memory" (in the therm of computer science) of life. Like we use 0/1 for digital memory of informations.

I find it fascinating. Wish you well.

6

GamemasterAI t1_j4tmcgj wrote

Probbaly targeting mesenchymal stem cells, the pluripotent precursor to cardiovacular cells.

0

ArandomFluffy t1_j4v02y5 wrote

from the article: >We packaged the ABE components in adeno-associated virus serotype-9 (AAV9) using a split-intein trans-splicing system to accommodate the large size of ABE8e and sgRNA6. AAV9 was chosen as the delivery system because it effectively infects the hearts of mice and large mammals (2, 4). To ensure cardiac specificity, we used the cardiac troponin T (cTnT) promoter to drive ABE8e expression.

6

Kakkoister t1_j4ty77d wrote

As other have mentioned, virally at the target location (heart cells last a lifetime). But also, you don't need to replace all the DNA. Just a decent majority to quell the expression of those genes.

3

marketrent OP t1_j4q95tm wrote

Findings in title quoted from the linked summary by Manuel Ansede, 16 Jan. 2023, EL PAÍS.

Excerpt:

>The gene editing techniques that have revolutionized medicine since 2016 could also be used to treat common heart diseases, the number one cause of death in humans, according to a study published recently by one of the world’s leading scientists, Eric Olson, from the US.

>His team was able to modify two letters – or bases – of the approximately 3 billion that make up the DNA of a mouse. This change was enough to silence a protein linked to multiple cardiovascular problems.

>Olson is cautious, but highlights the potential advantages of this new strategy: since heart cells last a lifetime, it is only a matter of making the change once.

>Olson, from the University of Texas Southwestern Medical Center, talked about his research to EL PAÍS via videoconference from Dallas, Texas, accompanied by a Spanish colleague from his laboratory, biologist Xurde Menéndez Caravia, co-author of the new study, who explained that the results of the first proof of concept are very promising.

> 

>The technique appears to be safe in mice; now, what comes next is to explore the possible long-term effects.

>The researchers modified the recipe for a protein called CaMKII delta, whose hyperactivation causes various cardiovascular problems such as arrhythmias, heart failure or damage to the heart muscle after a myocardial infarction.

>By changing two letters in the recipe, the resulting protein is not hyperactivated. Olson’s team used this technique in mice with cardiac damage after a heart attack, a phenomenon known as ischemia-reperfusion injury. The organs of the rodents recovered their function after the genetic editing of their cells.

>“As a therapy aimed at large population groups, it would be a revolution. We are talking about myocardial infarctions: potentially millions of people could be treated with this technique,” says Menéndez Caravia.

Lebek S., et al. Ablation of CaMKIIδ oxidation by CRISPR-Cas9 base editing as a therapy for cardiac disease. Science (2023). https://doi.org/10.1126/science.ade1105

27

Evianicecubes t1_j4t01ow wrote

“the technique is still not perfect and can produce some unwanted letter changes; this occurred in Eric Olson’s mice, although apparently without adverse effects.”

I am optimistic these off-target effects can continue to be lowered. Their existence will be a major hurdle going forward.

9

Theoreocow t1_j4s4pc3 wrote

Is that Jim Carry from 2078? Sorry mods

8

StolenErections t1_j4tfjf3 wrote

“Two letters”

It’s two amino acids.

6

ArandomFluffy t1_j4uzt1f wrote

Two letters were converted which leads to 2 amino acids being changed. So you are right, but quite unnecessary to point it out.

Methionine281 (ATG) and M282 were mutated to Valines (GTG) so only 2 A to G conversions.

1

StolenErections t1_j4y0zm0 wrote

Referring to them as “letters” is a part of the oversimplification that is so rife in academia right now. I am involved in the pipeline for new nurses, and I wouldn’t want 90% of these kids having any involvement in my own health care.

2

ArandomFluffy t1_j4z84sl wrote

This ''oversimplification'' is definitely not a problem here. It's journalism, it's supposed to be more simplified and even in the article they mention in the first paragraph that it's base modification that they are reffering to with that AND they examplain in tl;dr how it works (so that you know what level science journalism is done on). They could write out that they mean ''letters of the genetic code'' but contextually everyone generally familiar with it should be aware that that's alluded too.

And honestly if you want to be so overprecise on the genetics then saying that they exchanged two amino acids instead of two ''letters/nucleotides'' is practically more ''wrong'' because the difference in aa sequence is a downstream effect of nucleotide conversion and not how mutagenesis principally works.

2

AutoModerator t1_j4q7slz wrote

Welcome to r/science! This is a heavily moderated subreddit in order to keep the discussion on science. However, we recognize that many people want to discuss how they feel the research relates to their own personal lives, so to give people a space to do that, personal anecdotes are allowed as responses to this comment. Any anecdotal comments elsewhere in the discussion will be removed and our normal comment rules apply to all other comments.

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

1