The time I have spent in the Explorer’s Program has been both deeply informative, and interesting. We learnt about x-ray crystallography, electron microscopy, Leukemia, and more. One of the highlights of attending program, along with listening to the guest speakers, was learning about Gel electrophoresis and being able to perform it during the labs. We used it in a lab to identify dyes/indicators by observing how far they travelled, their colour, and which end they moved to. Gel Electrophoresis uses a cathode and an anode that separate mixtures pipetted into the wells through polarity. A dye or indicator with a negative polarity would be attracted to the positive anode and vice-versa. The number of possible dyes/indicators can be narrowed down by observing the polarity, distance and color of the dyes/indicators.
The progress of the dyes/indicators through the agarose gel after 12 minutes
In our second lab using Gel Electrophoresis, we made a cut in the gene B2M using Cas9 and 2 guide RNAs (gRNA), and then compared our 2 samples to regular B2M after running the gel box for 22 minutes. We pipetted the DNA ladder into the first well, the B2M sample into the second well, the first Cas9/gRNA1 sample into the third well and the second Cas9/gRNA4 sample into the fourth well.
The progress of the samples and the DNA ladder after 22 minutes
The B2M gene, Cas9/gRNA1, and Cas9/gRNA4 samples travelled approximately the same distance. They also all separated into three of their components and each of those components were the same colour as the corresponding component of the other samples. The yellow color is easier to see after removing the cap on the gel box.
DNA Ladder and samples in the agarose gel after the hood has been taken off
We used Gel Electrophoresis again during our Spot on CML lab where we simulated checking blood samples for Chronic Myeloid Leukemia. We added 100 microliters of the rehydration solution to a micro tube containing the patient sample and repeated this for the other patient samples. We then spent a minute incubating it at room temperature. After setting up the gel box, we added 2 microliters of loading dye to our samples and our controls, and then pipetted them into the wells.
The progress of the DNA ladder and the samples after running the gel box for ~30 minutes. In order from left-to-right are the DNA ladder, positive control 1, positive control 2, negative control, patient sample 4, patient sample 3, patient sample 8 and patient sample 7
As can be observed from the photo above, patient sample 3 is very similar to positive control 2. Therefore, 4, 7 and 8 all test negative for CML, but sample 3 tests positive for it.
I am grateful for getting into this program and for everything I have learnt while in it. It has been both fun and informative and I hope to be able to learn more in the future to build on what I have learnt here.