Understanding CRISPR-Cas9

Wow, they will really mess things up with this.

Does anyone have a pdf version of this lesson?

Thank you !!! so helpful!

thank you for this video, it helps alot :)

has any bacteriophages evolved to contain chi site.

Thanks so much for such a great video, really informative and easy to follow. This video and your one on human insulin have been amazing resources for my school research project. Thanks again!

great. good luck

This was very much informative yet explained in simple language video about CRISPR basic. It was more than helpful for me. Please make and upload explaining advanced forms of CRISPR (like prime editing, etc). This will help to build research methodology. Thanks.

gorgeous👏

Man! I love how you explained everything i have watched this video over and over again and again and still find something new about the CRISPER CAS9 , thank you for an amazing and detailed video
I hope you can teach us the complete biotechnology by this way!!😅
Thank you!! Cheers

Bei aware of human trafficking. Target Individuals are Test subjects for biomedicine, neurocience and robotic. A crime against humanity. Target Justice

New videos are always exciting to see!

Crisp and clear explanation on crispr

i found a the best explanation for CRISPR , it's well explained sir thank you , I'm looking forward for more videos like this

Excellent video - well presented. Easy to understand.

thank you so much you for your effort to explain for us this mechanisms, i was totally lost in CRISPR i have exm wich me luck.

What an amazing biologist, your enthusiasm is very contagious

Hello, i want to ask you something, could CRISPR Technology be a solution for clinefertel syndrome (47 xxy)?

That was a superb masterclass on CRISPR Cas-9, thank you so much for that.

Thank you. Thank you Andrew for your detailed and brilliant exposition of what actually takes place during homologous repair of dsDNA and insertion of foreign DNA through Cas9
CRISPR. I spent several hours looking at the schematics in books and articles and never could quite grasp how the homologous repair let alone DNA insertion occurred exactly. You are a superb teacher and I love the Brit accent.

That's true - the mutation will be near the cut site. But a scientist can usually design the sgRNA direct Cas9 to cut more or less anywhere (PAMs are quite common - they are NGG, in other words anywhere there are two Gs together will be a PAM.

You're welcome 😊

From what i've understand, DNA can only be cut few bases upstream of PAM. Then it seems that NHEJ method can only be used in quite limited part of the DNA. Is it still quite useful? or is there something that i've understood wrong?

Brilliant A real teacher indeed

There's not much more i can say that hasn't been said before, but this is the type of content that makes me go "How is this free?" Just awesome, and i can hope you make more if you can find the time to do so.

I have a question concerning the cut lenght from the PAM site. You mention the cut is made 'maybe 5 or 3 bases, rounded up to 4 upstream the PAM' But if it's anything other than 3 (or a multiple of 3, like 6) wouldn't that mess the codon it's slicing that extra nucleotide from? Does that entire codon become invalid or does the entire sequence shift by one base pair over and mess the entire thing? Genuinely curious, thanks.

Great video! I had a question - how do geneticists use the cas9 to target genes in human cells? I imagine there is no PAM on human genes. Is the sgrna enough to find targets without PAM?

You mention at the end that the bacterial DNA does not snip the viral genome due to the conflict of Chi sites already utilizing guanine residues. As it pertains to adaptive immunity I would think it logical that the 3 nucleotide upstream PAM of bacteriophages evolved such that the conflict with the chi-recognizing motif may provide an advantage to the virus during their co-evolution.

The virus was trying to get a replicative foothold by mimicing the essential chi motif sufficiently to sidestep obliteration induced by snipping. However, snipping the virus here would ge inefficient and energetically costly if the virus had already began replicating. An advantage subsequently corrected by the bacterial host, in adaptive response to the curve ball it was thrown. Better to lead all horses to the barn of their demise, rather than corale them one-by-one.

Is that what you were saying? I got a little lost at the end. It seemed the implication was that another adaptive mechanism was afoot.

In double stranded repair, when used for a lab created gene insertion, is there is a tell-tale crimp or identifying demarcation of this that's viewable under a microscope?

Dr.Andrew, It is my first time to write a comment to express my gratitude for someone, really really thank you for this masterpiece !

Amazing video. Saved my grade.

Great well done

W mans for this one

Thank you for making this video! Now I have a much bigger understanding on how CRISPR works. You explain everything clearly and it was easy to follow along with what you were saying

Thank you aloooot

Watched 6 vids on this topic and this video just set everything crystal clear...I was interested in knowing crispr...but now i feel like i can explain crispr...thank u🎉❤

I cannot stress enough how well you have explained this subject! Thank you very much!! Hats off to you, sir

Sources M8?

You are amazing, thank you! :)

Beautiful video

Thank you sir, the best video about cas9 i've ever seen

saved my research progect, major respect

Thanks a lot Sir. I'm feeling more confident about my seminar presentation because of you.

Fantastic video. Thank you

thank you a looooot!!!! you are amazing i wish the best for you you help me for my presntation thank you again Prof.😁😁

Thank you!

Thank you so much! This was thorough and super well explained. I am an undergrad in biology and this was at the perfect level for my understanding. The animations were also a great help in visualization.

Evidence for Intelligent Design. There’s no way this process developed by accidental means. You need DNA to create the proteins and enzymes. Chicken and the egg scenario.

Andrew! Thank you for posting this. I'm a fiction writer and songwriter and not a scientist by trade or training, so I'll admit that there was a reasonable amount of information that I'll have to rewatch several times before I'm remotely confident I understand it. However, what you did here, bridging the gap between the oversimplified videos out there and the overly-technical videos was amazing and a gift to us all. Now, I have a much better understanding of CRISPR-Cas9's mechanisms and a little more insight into the whole gene therapy process. As an added bonus, your enthusiasm is infectious and absolutely sells the whole video! I do have a question for you. If scientists wish to introduce a new genetic sequence into a person's DNA (what I assume gene therapy entails), how do they ensure that the engineered sequence is found and used by the cell's repair mechanisms--particularly, in Homology Directed Repair? Is it a matter of deploying a large enough concentration of those sections so that the odds are high? AND would be a typical vector or means of introducing that desired repair sequence into each cell? A viral vector?