Understanding CRISPR-Cas9

This video is a deep-dive into CRISPR-Cas9, but it takes the time to explain terms and concepts carefully, so that students who are new to the topic will understand it, and those who already understand what CRISPR is, but have unanswered questions will find the depth of answers they are looking for.
Now that VCAA have intimated that they expect students to have more than a superficial knowledge and understanding of CRISPR (for example they have to know about PAM sequences), many of the videos and websites I'd once have recommended are no longer sufficient because they leave out details in an effort to make the concepts easy to grasp. Others which do include details are unassailable to students because of the prerequisite knowledge and terminology they assume.
That's why I made this video. It goes deep (really deep, actually), but I hope that stepping through it slowly, and explaining terminology as we go will make it a valuable resource for students really wanting to understand.
It covers both the way that bacteria use CRISPR-Cas9 as an adaptive immune system, and the way it can be used for gene editing by molecular biologists. It also answers lots of the questions that people have when learning about CRISPR-Cas9, such as:
- is there a difference between gRNA and sgRNA? (and what is the difference between crRNA and gRNA?, or between cr:tracrRNA and gRNA?)
- how does Cas9 differentiate between 'self' and 'non-self'
- why doesn't Cas9 cut the spacer in the bacterial CRISPR array?
- why don't Cas1-Cas2 make spacers out of the bacterial DNA?
- how is Cas9 used to 'knock out' a gene.
- how is Cas9 used to insert a gene at a specific location using the cells DNA-repair machinery.
etc.

[@brandonmansfield6918]

Man! You are one heck of a great teacher. If we could all shrink ourselves and see everything in our cells and shrink even smaller to see the mechanisms DNA uses, you would be the perfect tour guide because you explain things that well.

[@andrewdouch]

That's a very creative way to say 'thank you'. You're welcome! - thanks for the kind words. I'm glad you found it helpful.

[@og_philip97]

I totally agree I am currently learning about CRISPR-Cas9 at Uni and you have been way better than my professors. Thank you.

[@andrewdouch]

haha that sounds like a fun job!

[@hawks19_65]

@@andrewdouch hey andrew i must say you are the best at explaining these complicated concepts. In fact I have a sac on wednesday based on this and manipulation techniques and you have helped me understand all these and i feel like i’m more confident because of you. Thank you so much

[@daisytoromanzano8865]

@@andrewdouchIs CRISPR-CAS9 used in covid vaccines?

[@hanspozo8563]

As you said, your video really fills the gap between those simple videos for the "common people" and those, who are made from experts for experts. Thank you!

[@Hanking-Yo-Schrader]

Sir, I was so lost in CRISPR and didn’t know where to start and where to go. This is hands down tue best video on the topic. You went sufficiently into depth while keeping everything clear and concise. I would really appreciate next a detailed video on Prime Editing similar to this one, and comparing the 2 strategies, and talking about the problems with CRISPR such as high indel ratio, etc. Keep up the good work!

[@andrewdouch]

Glad it was helpful!

[@sebastianderien5823]

I am speechless. I think with a teacher like you, biology would have been on the top of my preferred classes. I wish you all the best.

[@andrewdouch]

So nice of you

[@user-ld6nf6mr6o]

You really gave the intuition to the whole CRISPR -Cas9 thing and cured the questions that were bugging me before , now its clear to a very good extent. Very grateful for this

[@Wideelf]

This video actually saved me! You are the only reason I'm making it through year 12 biology 🤣🤣

[@peterstevens3395]

The presentation is a perfect marriage between hitting all the key points, conciseness, proper elaboration, giving all the necessary details. Excellent job!

[@andrewdouch]

Thanks Peter - that's a nice review! :)

[@peterstevens3395]

You're welcome, Andrew! Keep up the good work.@@andrewdouch

[@DanCasciano]

Thank you for that very understandable description of the CRISPR-Cas9 system. Your explanation and your graphics are super.

[@andrewdouch]

Glad you like them!

[@rehamhassan576]

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

[@andrewdouch]

you're welcome! I'm so glad you found it helpful :D

[@s_tsering]

I am glad and thankful that this video exists.

[@andrewdouch]

thank you! I'm glad you liked it

[@ansotica9531]

wow, what a great video. i've been looking for it for a long time and now there's finally one. without whiteboards, bad drawings, superficial subject matter and confusing slides. i'm studying biology and never understood the mechanism when my professor explained it. i then neglected it while studying. now i failed an exam repeatedly and have to go through the topic again. and you explained it so incredibly well, with all the details one needs to know, but not toooo detailed. thank you so much for that. i feel well prepared and hope there will be a question about CRISPR/Cas9 :)

[@andrewdouch]

You're welcome. I'm really happy to know it helped you! Good luck on the test.

[@cryptapocalypse]

Andrew- outstanding presentation. I had some molecular biology training, but rarely if ever received instruction in the methodical and organized manner you use here. Thanks very much for taking the time to do this.

[@andrewdouch]

You're welcome :)

[@austintao8763]

This is really an amazing video! Thank you so much for taking your time carefully preparing and making this video!!

[@drdesy1]

Brilliant A real teacher indeed

[@davidliu3128]

This is the most splendid video on CRISPRCas9 system I have ever encountered. You have solved every question I have got on this topic! Thank you so much!

[@andrewdouch]

Glad you liked it! Cheers.

[@noimpactbeats2888]

Outstanding explanation. Going to start working in the lab next week, exploring the possibilities of CRISPR Cas 9 gene editing in patients with heart disease. Thank you for the refresh !

[@andrewdouch]

You're welcome. Cheers

[@HannatIsmail]

I have read many articles and protocols and this is the only resource I have come across so far that explained in great detail! Thank you!

[@andrewdouch]

You're welcome :D I'm glad it helped

[@jacekyle3131]

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🎉❤

[@andrewdouch]

You're welcome! Thank you for the lovely comment 😊

[@naveedarshad9432]

Good Evening. I am also a teacher but your smile and such innocent communication, wonderful for me because students never get boring in such topic like crispr.

[@andrewdouch]

So nice of you

[@samstern1185]

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

[@andrewdouch]

Thank you for taking the time to leave such a kind comment. I'm so glad you found the video helpful 😀

[@mansidalal7926]

OMG! What a full-package video of animation & theory both. Very nicely described, Never thought this topic will be a cakewalk for me. Thanks a lot for making this.

[@andrewdouch]

you're welcome :D

[@carlosmaldonado967]

Amazing video! It is hard to find such specific information and detailed animations and explanations of these concepts. Invaluable! Subscribed.

[@andrewdouch]

Glad it was helpful!

[@sarahkribben1521]

Wow! that was awesome! Took me about 90 Minutes to work and write through this video, but I can‘t imagine anyone is doing a better job explaining this than you! Thank you so much! Definitely a new follower here 😊

[@andrewdouch]

Wow, thanks! Anyone who can listen to my voice for 90 minutes deserves a medal ;)

[@helenapetrou7]

Thanks for such a detailed and engaging explanation Andrew! Has helped me so much

[@ukistoki5376]

Thank you so much, the video was so helpfull! It is actually the most informative and detailed explanation I have found. Its amazing how u deeply understand all the process step by step without skipping any crucial information. Im so glad I found your channel. You're doing an amazing job

[@andrewdouch]

Glad it was helpful!

[@ytmadhavan]

Great teaching, Andrew. Thank you for helping me understand the CRISPR concept.

[@alanlee960]

This is awesome and professional. Thank you for explaining those concepts deeply and thoroughly

[@nuraziz1669]

The best crispr-explanation video 🎉

[@andrewdouch]

Glad it was helpful!

[@andrewdouch]

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.

[@zackkykada567]

the video served it purpose, thanks a lot mr andrew .

[@raptorgamer9289]

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

[@andrewdouch]

Great to hear!

[@vipikuttu7383]

One of the best, explanation for CRISPR, hats off 🥰❤️

[@msf7291]

Most excellent! Thank you. This is the best explanation of this topic I have had yet.

[@karimmunoz2422]

i finally understood how CRISPR-Cas9 works!!! thanks for making this video!

[@andrewdouch]

You're welcome!

[@lucasvandijk1615]

1 video that contains everything I needed to know with the best animations ever, amazing wow. I would pay for this

[@andrewdouch]

you're welcome - glad you liked it. (those animations took me ages to make so I'm really glad you found them helpful)

[@ghassanhaddad5446]

you literally saved my life! you explained this really detailed and simple at the same time. it was really really helpful. thank you sm!

[@andrewdouch]

You're very welcome!

[@robertpawlsoky2910]

just great, your explanations are terrific !

[@andrewdouch]

Glad you think so!

[@samwaelarmoush2321]

This was incredibily helpful! I am writing a term paper on CRISPR-Cas9 and its use for curing genetic disease such as muscular dystrophy. I was reading many research papers but could not keep up with the terminology and the heap of knowledge in them. This video gave a great foundation and I feel far more confident in approaching research papers. The visuals and explanations were elegant and show just how intricate and incredible life is. Thank you!

[@andrewdouch]

Glad it helped you out :D

[@rodrigokuszek]

Wonderful way to explain everything in a bit more than 30 minutes. You are amazing Andrew! And thank you so much, I needed this

[@andrewdouch]

Thanks for the feedback - I'm really glad you found it useful.

[@vic7181vic]

Wow! The greatest video ever! In every regard, it was the best. Very deep and very understandable. Thank you so very much. Please teach us more!

[@larshaji6117]

I have never seen an amazing explanation like this, u are a phenomenon

[@andrewdouch]

thanks for that :D

[@KaliostroA]

Great explanation! Thank you

[@JenniferHort]

This was so helpful - I'm a clinician working through a clinical genomics qualification and this was just the right level for me!! You are an excellent teacher, thank you so much.

[@andrewdouch]

I'm so glad! - thanks for your comment it made me smile.

[@doraobodo5011]

This was amazing and you are an amazing teacher! I am a new FAN!

[@PrettyPilatesPrincess]

This was an awesome video, and you are a very engaging teacher (much needed for a 30 minute biochem video and my short attention span!) Thanks for this great video :)

[@andrewdouch]

Glad it was helpful!

[@emmy.vosper]

My biology exam is on Friday, but im too excited to just watch Douchy all week so I can’t even feel stressed

[@andrewdouch]

haha - I hope the exam went well!

[@arcticwolf5041]

I passed my one of my honours tests because of you. Thank you so much. Great teacher!

[@andrewdouch]

That makes me happy to know! Glad I could help

[@TheBrandedAffiliate]

Amazing and in-depth, made it super simple and easy to understand, love you douchy

[@andrewdouch]

Glad it helped!

[@dom6783]

best video on CRISPR - PERIOD

[@andrewdouch]

Thanks Dom :)

[@sarayugopal9363]

For the first time understood the topic from the scratch to more than expected to know. Wonderful explanation

[@andrewdouch]

I'm so glad it helped you out

[@abdelmeguidaly2924]

You are an amazing educator, i am a year 2 biomedical science student and i have come across only a handful of professors or teachers that are as good and actually want to educate like you. Thank you very much.

[@andrewdouch]

Thanks for that. It means a lot :)

[@eshatambe3920]

Thank you so much for making this video. This video really serves its purpose and it helped me a lot to understand the concept of CRISPR and break repair mechanism in detail. I truly appreciate the time and effort you took to put this highly informative video. I would also like to request you make a similar kind of video on Next Generation Sequencing. I have seen a lot of videos on NGS but they are quite complicated. Thanks a lot.

[@dhabyamajid1237]

This was amazing. Thank you.

[@kristianrodd5809]

Very well explained. Thanks

[@carmenkerr1237]

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.

[@andrewdouch]

Glad it was helpful!

[@whatzittuuyah7640]

our friend is a microbiology mmmajor(??), we've just had an interest in it since we were a kid, and she sent us this video. We were a *little* nervous at first that it'd be a hair beyond our understanding, but it came across all clear!! This stuff is so neat, it's never gonna stop being the coolest that chemistry taught itself programming by exploiting physics and now life exists. It's all so deeply intricate - an incredible dance of interlocking elements and systems, and it just!!! exists!!!! naturally!!!!! Anyways, this video is incredibly informative and effective at bridging that gap. Even for someone where the terminology isn't familiar, the explanation gets the idea across clearly and in detail such that an understanding is developed whether or not the particular vernacular sticks. Very well done!!

[@EliEriSak]

One of my favourite instructional videos. Already visited this one thrice for refresher of the nuances! Hope to see more such content. Thanks Andrew x

[@andrewdouch]

You're welcome! That's very kind of you

[@Temitope_Lawal]

I'm glad I found your video. You're a blessing to all students Crispr-Cas9 has caused headache to including me.

[@andrewdouch]

Glad to help

[@DanyMLGJJB]

best CRISPR education by far！

[@dawbool9552]

As somebody of the general public just eager to understand the world around him and within himelf, I am very grateful for this going-to-more-depth video. After perusing this video at least three times and consulting some school textbooks for some basics, I was able for follow and understand. What an amazing and ingenious nano-world! And what an admirable and joyful manner of conveying knowledge! Chapeau!😊

[@andrewdouch]

Thanks for that. Glad you found it interesting:)

[@sam.f3002]

great video mate, made me understand everything so easy when my teachers in uni couldn't... thanks!!!!

[@ting1654]

Thanks a lot! This video really helps me know better about CRISPR, and your teaching is fabulous!

[@andrewdouch]

You're very welcome!

[@dietsoda1093]

Incredible video, greatly increased my understanding, and your energy is contagious

[@andrewdouch]

Glad you enjoyed it!

[@user-kw9ns2dm9k]

Amazing explanation, you are really scientist

[@snehalmurumkar4953]

Thank you soo much for making CRISPR-Cas9 understanding so easy!

[@andrewdouch]

Glad it was helpful!

[@senatadesse7732]

Thank you 🙏🏾 a great lesson to understand CRISPR

[@firstep1363]

HEY !!! YOU REALLY HELPED ME A LOT !!!! A TONS OF APPRECIATES FROM ME !!!😂 THANKS A LOT PROF !!!!

[@confusedsoulps-gp6nt]

Really nice video. Also you are a great teacher!

[@andrewdouch]

Thanks :D

[@javiersanjuan296]

Amazing presentation! Thanks for all your time and effort!

[@andrewdouch]

I'm glad it payed off for you :)

[@user-pc2dm9ky7p]

OMG Thank you so much!! for CRISPR Cas-9, even though I read the powerpoint from the class, I still did not fully understand since it is very complicated and difficult mechanism to understand. Your video solved this problem, and I loved how you explain these step by step and those little details very clearly!!. It was so helpful for understand cas9 and even details of this process. Thank you!!!:)))))

[@andrewdouch]

You're very welcome!

[@nurjiskhatoon1807]

Such a nice explanation....how much hardwork you have put in.....that's unbelievable such fastidious details....bravo for such a great hardwork....really appreciated

[@andrewdouch]

It's my pleasure

[@brotosarirahayu5045]

this is really a new topic for me, thank you for explaining it so clearly

[@andrewdouch]

You're very welcome!

[@vibhavagarwal6042]

Amazing video Andrew! I have an assignment to give a presentation on CRISPR to my class and this video cleared the entire concept and made me confident enough to present it! Thank you! Also it is so heartening to see you enjoying teaching it, you almost seem like a kid who is about to see his Christmas presents haha...

[@andrewdouch]

Glad it was helpful!

[@clanastral117]

I LOVE this explanation 🤩 your amazing.

[@andrewdouch]

Thank you! 😃

[@dangoldberg4160]

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?

[@andrewdouch]

Hi - you're welcome. I'm glad you found it helpful. You are right that by putting a large number of copies of the DNA one wants incorporated into the cell, increases the chance that the repair machinery will use one of those as a template for HDR. But it's not a sure thing by any means. In fact the success rate is quite low - but still much better than traditional methods. The DNA is usually put into the cell by microinjection or electroporation.

[@mariociencia12]

OMG! I Finnaly understood not only CRISPR, but also homologous junction repair! Thank you very much!

[@andrewdouch]

You're really welcome :D I'm glad you understood!

[@user-ko3ln9cc2z]

OMG this video, yes perfect, for my exam i needed to learn how this works and needed to learn a paper written by fellow classmates, i dont think they saw this video bc this explanation is a 1000x better more understandable! Thank you!

[@andrewdouch]

So glad you found it helpful to you.

[@fatemastersleepy4197]

THANK YOU SO MUCH MAN YOU HAVE NO IDEA HOW CONFUSED I'VE BEEN FOR THE PAST FEW WEEKS ABOUT HOW THIS WORK, my exams are in 2 weeks and we didn't learn this properly in school < 3

[@fatemastersleepy4197]

Also, I do have a small question, won't the bacteriophage evolve over time to have chi sites making CRISPR-Cas9 ineffective?

[@andrewdouch]

@@fatemastersleepy4197 Great question. You’d think so, right?

[@airwolfcentral169]

Thank you very much. Year 12 unit 3/4 bio student was extremely helpful and well articulated! Underrated channel will recommend to other classmates!

[@andrewdouch]

Cheers for that. 👍🏼

[@joshbuild1062]

I personally have no exams I'm doing on this topic, I'm just a 15 year old who got interested in the topic and wanted a deeper explanation than most youtube videos offered, and I'm really glad I came across this video because it's an amazing explanation, diagrams that really helped me understand what's going on, and your teaching is awesome. I really liked how you addressed potential questions and I hope one day i could be able to learn how to teach others as good as you do because I love teaching things I've learnt to my friends. Just a few questions, I remember hearing that some cells prefer non homology or homology directed repair when given the option for both, do you have any explanation why that may be? Could it be due to availability of more or less homologous pairs or such? Then I'm not sure if this was mentioned, but what process allows the nuclease domains to cut the DNA. Lastly, I keep on hearing gene drive in the case of genetic engineering of mosquitos, is gene drive essentially just meaning all other homologous strands of DNA contain only a certain allele of the gene, as such when the other allele is damaged/cut it replaces it with the desired version and the cell essentially eliminates the cut allele for the rest of it's life cycle. And why is gene drive just exclusive to insects, and doesn't occur in mammals? Is there some other mechanism in mammals that ensures the homologous DNA can have either version of the alleles. Thanks alot for the vid, I've subscribed and liked the video, hopefully helps in more people seeing it, and I'm looking forward to watching more of your videos.

[@andrewdouch]

Thanks for the feedback - I'm glad you enjoyed it. Also glad you are doing biology for fun. That's the best way imho!

[@lukebeckstrom2350]

its great that you have this interest, but if you're wanting real answers to your questions, I'd recommend you ask specific questions in your research. its quite hard to follow what you're asking, especially with unnecessarily long sentences.

[@nurjiskhatoon1807]

With this smiling face difficult things explained beautifully simply....I need such a good supervisor for PhD do you take PhD students

[@zhangzhengyifan6117]

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

[@andrewdouch]

Glad you liked it!

[@JedHollisterGirl]

Wow thank you that is an excellent explanation

[@brianmckittrick8665]

Andrew- thanks - for me you did in fact bridge the gap between not enough and too much detail. And yes it is fascinating.

[@andrewdouch]

Glad you found it helpful!

[@PetreSmith]

This is superb! Thank you.

[@andrewdouch]

Glad you liked it!

[@honestabe1940]

I'm retired military, retired state voc-rehab and now taking the cellular biology trip. Thanks for the ride!

[@andrewdouch]

You're welcome

[@Austinicy]

Awesome video!

[@andrewdouch]

Thanks!

[@tprincipato]

Excellent presentation

[@andrewdouch]

Thank you! Cheers!

[@user-yu4lz8ts4m]

You are a legend, thanks so much!

[@andrewdouch]

You're welcome!

[@WanC9]

Thank you so much. This is the best explanation.

[@andrewdouch]

Glad you think so!

[@gooddy9928]

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

[@andrewdouch]

That's great - I hope the presentation went well 😊

[@gabrielapereira9776]

Thank you so much for this video! I was reading Charpentier and Doudna article but it was a bit difficult to understand some informations... now everything is making sense. You are an amazing teacher.

[@andrewdouch]

I'm glad it helped 😀

[@c.b.nikhil4876]

Excellent Andrew. I was thinking of doing something like this. But you have already done an exceptional job. 👍👍👍

[@andrewdouch]

Thanks! :)

[@robertjones9566]

Thank you thank you thank you for being and amazing teacher. Thank you for transforming complex information into something understandable.

[@andrewdouch]

You're welcome Robert. Thanks for kind words. I'm glad you found my video helpful.

[@Wendyswimmer]

Fantastic video. Thank you

[@andrewdouch]

Glad you enjoyed it!

[@katenicholls5301]

Thank you SO much for this class. It was super helpful. You are a wonderful teacher.

[@andrewdouch]

Thanks!

[@gershwinjoy7877]

A. finest video which explains the concepts well ( really struggled to find out about PAM and NGG,which is well detailed in this video Thanks ( also it helped me for my essay a lot )

[@andrewdouch]

Glad it helped you :)

[@user-cu5ty8re9w]

Thank you very much for the helpful explanation dear Andrew.

[@andrewdouch]

My pleasure!

[@user-jr9tx9sy1m]

Thank you, sensei.

[@andrewdouch]

Any time!

[@omarc4ut]

Wow, what a great explanation. Thank you very much for the information. Please keep up the good work. 👍🙏

[@andrewdouch]

Thank you! Will do!

[@theone-zh5pt]

Thank you very much! Although I am a foreign English speaker, your explications were very easily understandable to me. (I am sorry for grammar mistakes) In school, I want to present a subject in genetics and CRISPR-Cas9 is quite amazing! Even though there is no explication in our biology book... Perhaps, if it´ll works, I will present CRISPR!! Thank you, finding some good explications on the internet is not easy but now I understand!!

[@andrewdouch]

You're very welcome!