Manipulating someone’s genetic code may sound like something straight out of a science fiction movie, but scientists today are using technology called CRISPR to do exactly that. Scientists are using the genetic codes from a wide variety of lifeforms like trees, bacteria or even viruses. CRISPR specifically edits the small pieces of DNA that pair up with one another called nucleobases. Nucleobases are the alphabetical code made up of As, Ts, Cs and Gs that when paired up with one another forms the helical shape of DNA. When those pairs of alphabetical code come together, they form a specific sequence that has a specific function called a gene. For example, one short sequence of pairs could encode for the function of an apple to have a red color. Scientists edit these sequences by using a protein called cas9. Scientists could plant the short sequence of the red gene of the apple onto the cas9 protein and the protein would be able to enter an apple cell, locate the same exact short sequence of gene and cut it. The protein cuts both strands of DNA by recognizing a particular pattern of 2-4 pairs of letters and only at these points (Barrangou and Doudna 2016).
Once the DNA is cut, the apple cell has built in mechanisms to try to repair itself but it would make a lot of mistakes. Since the sequence of pairs of the red gene could not be repaired, then the apple won’t be red. Scientists can edit the way the apple cell repairs itself so then the broken red gene could be rearranged and fixed to turn into a purple apple (Redman et al. 2016). Or if scientists wanted to make the apple more sweet, more sour, more tender, more resistant to bugs or the environment they would be able to by using the changed repair method. This could be used to help grow plants in a changing climate, help repair broken genes that cause genetic disorders or make bacteria less resistant to medicines. In our physical lab portion of this class, we test this technology on bacteria by making it resistant to an antibiotic. We had to target the specific gene that binds to the antibiotic to make sure that it can’t bind properly. Since it can’t bind properly to the antibiotic, the bacteria won’t be affected by it. This real life application proves that CRISPR technology is convenient, relatively easy to do and is cost efficient for an entire class. It is the future and essential to our survival as the effects of antibiotic resistance and climate change become more prevalent.
References:
Barrangou R and Doudna J. 2016. Applications of CRISPR technologies in research and beyond. Nature Biotechnology. 34: 933-941. doi: https://doi.org/10.1038/nbt.3659
Redman M, King A, Watson C, King D. 2016. What is CRISPR/cas9?. Archives of Disease in Childhood- Education and Practice. 101:213-215. doi: http://dx.doi.org/10.1136/archdischild-2016-310459.
