A Closer Look at CRISPR
I've talked about crispr in the past a couple of times and while this genetic technology will not be playing a primary role in my project, I think there is value in discussing exactly how it works.
Clustered Regularly Interspaced Short Palindromic Repeats, commonly known as CRISPR, is a genome editing technology that allows for the permanent modification of genes within organisms. Depending upon the model/type of crispr, this technique for gene editing uses segments of prokaryote DNA, usually taken from bacterial cells, to detect and destroy DNA from further attacks by similar viruses. That said, the future of crispr is most favorable in the realm of genetic disorders. As described by Dr. Jennifer Doudna, coauthor of A Crack in Creation (An absolutely wonderful example of masterful scientific narrative), crispr - in this case, with respect to the cas9 bacteria - functions with a cut-and-paste mechanism. The bacteria finds its predetermined location, splices the genetic information, and inserts its pre-purposed snippet of prokaryote DNA.
In terms of my project, I'm using crispr to help me set up the worm populations for my experiment. Since it would be rather difficult to find worms with Alzheimer's in the soil of my backyard, I have used crispr technology to synthesize genetic snippets of mutations related to plaque buildup in the brain. Then, I simply injected the protein-amino acid chains into the worms. Because I injected the sequence into fertilized eggs before the worms laid them, I theoretically acquired an entire population with the desired genetic backgrounds. Although, sometimes this doesn't work correctly as I learned towards the end of the summer.
On the backside of things, you're probably wondering how we can tell that a worm has retained its assigned genes - that would be PCR or Polymerase Chain Reactions. I have a whole journal on this procedure so I won't bore you by explaining it again, but to put it simply, PCRs are like that feature on Google Translate where it reads you the word out loud. I see the word on my screen and I can probably sound it out but the voice feature affirms that I am pronouncing it correctly. Similarly, I know which proteins I injected into my worm population, but PCRs are confirmation that what I wrote down in my lab notebook is actually what I'm seeing under the microscope. It's checking my work for me. At that point then, I will either have results confirming my genetic manipulation, or a red flag that says, go back, the reaction may have gone wrong - the latter of which is what happened the first time I attempted setting up my experiment.
Anyway, the point is, crispr is a genetic technology that can be used in a myriad of scenarios to manipulate genetic sequences. The opposite technology then, to confirm any work done in the vein of crispr is completed through PCR.
In other news, I've got a field trip tomorrow to hear a lecture by Sam Rhine on genetics for my biology class, my first committee meeting, and an interview with someone who has been diagnosed with a combination of two neurological disorders. So yes, since Ben asked, it will be another busy Tuesday with a journal likely attached. In terms of my committee meeting, I'm a little bit nervous but I feel that I did as much preparation possible because I've been scheduling individual meetings with my committee members and doing everything in my power to make this abstract and introduction the best they can be. The interview which I am completing after school is for my next SDA. In my previously published goal post, I mentioned that I wanted to do something that delineated the worm-human interface and what significance C. Elegans research holds on a human level. I am planning to record a podcast with my personal take on the progression of these levels of scientific research and incorporate some parts from my interview. So I guess things are moving along, keep your fingers crossed that I don't mess up too badly...