Science Assignment: Reviewing Innovative Scientific ResearchOfCRISPR-Cas9

Question

Task: Summary:
In this science assignment, you are required to write a brief (1500 word) literature review of a field of science that is undergoing pioneering innovation. Introduce the topic, including some background, and the current scientific progress in the field. Importantly, your report should identify knowledge gaps in the field.

Content:
At its simplest, a scientific literature review is a critical summary of the current status of a research topic. This simple idea gets considerably more complex when you apply your scientific thinking and start analyzing your sources in detail.

Your report needs to:
i) Provide a clear statement of the research topic you are reviewing and why it is important e.g. CRISPR-Cas9 has the potential to revolutionise biological research across a diverse array of fields, from crop production to drug development (Smith 2020). Some of the most significant recent innovations have occurred in its application in modifying the human genome…

ii) Introduce the main ideas, theories and concepts relating to your topic
iii) Critically evaluate the research. This includes comparing and contrasting findings, arguments and theories. Are there areas of disagreementControversy
iv) Critically evaluate sources. Are there any issues with methodology (e.g. sample size) Do the authors make important assumptions (implicit or explicit) Is there evidence of bias
v) Identify knowledge gaps in the literature relating to your topic.

Answer

Introduction
The aim of thisscience assignmentis to provide a review of the latest innovative scientific research for understanding its research process, sources along knowledge gaps within the research process. To effectively understand the research process, the innovative scientific research of the recent time that is CRISPR-Cas9 has been selected. CRISPR is eventually becoming an essential tool within biological research and it is also known as the bacterial immune system against attackof viruses. The research is performed for understanding the genome editing process and gene mutation for fighting human disease.

Research topic and background
The research topic is considered to be CRISPR-Cas9 as it has the potential to revolutionise biological research across the diverse array of fields that is from crop production to drug development. The recent innovation of this research is primarily based on its application in modifying the human genome which is a system that is being used to modify a genome in a targeted manner(Moro et al., 2021). The “CRISPR-Cas9” was generally adapted from the naturally happening“genome editing system” within bacteria. It can be evaluated that the bacteria capture scraps of the DNA from attacking viruses as well as use them to create DNA section that are eventually known as “CRISPR arrays”. CRISPR-Cas9 is the microbial adaptive immune system that eventually uses the RNA conduct nucleases for clearing the foreign genetic elements.

The “CRISPR-Cas9” is the best characterized that consist of the nuclear “Cas9”, in this the “crRNA array” that eventually encodes the guided RNAs as well as required “auxiliary trans-activating crRNA” that eventually assist the processing of the “crRNA array” into separate units(Haapaniemi et al., 2018). Moreover, the RNA also combines to the “Cas9 enzyme” and in the bacteria, the customized RNA is used for recognising the “DNA sequences” and the “Cas9 enzyme” eventually cuts the DNA at the targeted spot. Genome editing is considered to be the great interest in the anticipation along with the cure of human disease. This research is quite innovative for developing suitable technological measures to deal with the human gene and their disease by maintaining the RNA and the DNA.

Critical evaluation of research
The CRISPR-Cas9 research eventually deals with genome editing which involves the adaptive activity in the design of the nuclear for maintaining the system of the human body(Liu et al., 2019). There are other genome editing technologies that can be effectively compared with the CRISPR-Cas9. It can be effectively understood that other designer nuclease technologies like the ZFNs along with the TALENs the “Cas9” can effectively facilitate the targeted “DNA DSBs” at the precise loci of attention in the genome as well as it helps in stimulating genome editing with the help of NHEJ or the HDR(Ran et al., 2013). Moreover, Cas9 present several potential benefits over the ZFNs as well as the TALENs which eventually include the easy method for customization along with the higher targeting efficiency as well as the ability to facilitate the multiplex genome editing within the system. In terms of ease of customization, it can be effectively understood that Cas9 is quite easy to retarget it to the new DNA sequences by the simple process of purchasing a pair of oligos“encoding the 20-nt guide sequence” but the“TALEN” for the new “DNA sequence” has eventually required the construction of two new “TALEN genes”.

In terms of the cleavage pattern, it can be seen that cas9 is eventually known for making a rounded cut between the 17th as well as the 18th bases within the target sequence, whereas, TALENs cleave non-specifically is considered within the “12-24 bp” that is a linker connecting the pair of the “TALEN monomer-binding sites”. Again, in terms of editing efficiency, it can be understood that Cas9 along with the TALENs both have been shown to effectively assistwell-organized genome editing within a variety of cell types along with the organisms(Cullot et al., 2019). There are numerous controversies related to this research and one of the most controversial issues that eventually surround the potential use of CRISPR-Cas9 is to create genetically engineered humans. One of the controversial issues is the CRISPR-Cas9 baby scandal which is being performed by engineering mutation into the human embryos(Gribben, 2019). There is no definite evidence of this experiment but it has attracted much attention that the incident might alter research for years to come. This research was done on the twin babies where the gene-editing was performed to resist the HIV infection and it was presented at the 2018 International summit in Hong Kong. The use of this research and technology has been developed to deal with the disease within the human being by performing gene mutation.

Critical evaluation of sources
The research is effectively performed on the plants and animals for understanding the gene mutation to deal with various diseases within the human being. One of the sources that could be understood from the various research of “CRISPR-Cas9” is the use of “CRISPR-Cas9” in the twins' babies' embryos to fight the HIV infection(Adli, 2018). The researcher was the Chinese researcher He Jiankui and this research created a huge storm in the media. Though there is no proper evidence for the research the news was over the media and provides a huge obligation to the researcher. The research was effectively made on the babies and this is not legally activated among the research field and for that the researcher was penalised for the activities that he eventually performed. Other research is also performing in this system that is associated with cancer research as well as therapy(Song et al., 2019). This method allows the scientist and the researcher to maintain powerful functional genomics tools for discovering novel targets for cancer therapy. This research source effectively helps to develop a view on cancer therapy for the improvement of human health conditions and maintaining their value within the research process.

Another source that could be effectively understood from the research activities is the “gene drive” research to effectively control enveloping animal species. It can be effectively understood that gene drive helps in reducing the invasive animal population within the country. Scientists are developing a suitable and effective method that helps in the mutilation of animal genes for controlling their population within the country. The primary assumption that was being made for the importance of the research on CRISPR-Cas9 is developed effectively by maintaining the process for dealing with the situation in the most effective and suitable way(Mei et al., 2016). There is various other functional testing as well as analysis that eventually help the researcher to perform their activities and provide the valuable information to develop the genetic mutation process within the scientific field. The research is being performed for dealing with the situation in the most effective and suitable way to understand the process and develop various sources in performing the activities. Moreover, the double standard DNA, as well as RNA sequence, can be effectively edited by using the “CRISPR-Cas9 system”(Rosenblum et al., 2020). The sources are effectively developed for maintaining the situation and scientific research activities for developing gene mutation to gain effective activity within the research field.

Knowledge gaps in the field
The CRISPR-Cas9 can be effectively targeted to the specific “genomic loci” with the help of a “20-nt guide sequence” on the “sgRNA”. It can be understood that the only obligation for the assortment of the “Cas9 target sites” is to be the occurrence of a “PAM sequence” that needs to be directly “3’ of the 20-bp target sequence” (Zhan et al., 2019). Furthermore, it can be also understood that each of the Cas9 orthologs is having a unique “PAM sequence”. For example; “SpCas9” eventually requires a “5' NGG PAM sequence”. It can be seen that this PAM necessity does not rigorously limit the targeting series of the “SpCas9” within the “human genome” and these marked sites can be eventually found on average “every 8-12bp”. Another knowledge gap that could be effectively understood from the research is the risk of off-target editing that eventually slow down the application of the “CRISPR-Cas9 system” within “human medical therapy”(Bak, Dever, and Porteus, 2018). It can be also seen that the low efficiency of the HDR eventually slow down the wide application of “gene knock-in” or replacement. This method is limited in the specific cases in the recent time and also the base editing that avoid the “HDR pathway” is considered to be more proficient and for that, it became the hotspot of the recent research.

Conclusion
It can be effectively concluded that “CRISPR-Cas9” was generally modified from the naturally happening“genome editing system” within bacteria. It can be also concluded that the bacteria capture scraps of the DNA from attacking viruses as well as use them to create “DNA segments” that are eventually known as “CRISPR arrays”. Moreover, it can be also concluded from the research paper that Cas9 present several potential benefits over the ZFNs as well as the TALENs which eventually include the easy method for customization along with the higher targeting efficiency as well as the ability to facilitate the multiplex genome editing within the system. Furthermore, the paper concludes the view that the risks of “off-target editing” eventually slow down the application of the CRISPR-Cas9 system within “human medical therapy”. Scientists are developing a suitable and effective method that helps in the mutilation of animal genes then gene mutation for controlling their population along with the disease within the country.

References
Adli, M., 2018."The CRISPR tool kit for genome editing and beyond", Nature Communications, 9(1).doi: 10.1038/s41467-018-04252-2. Available at: https://www.nature.com/articles/s41467-018-04252-2 (Accessed: 7 October 2021). Bak, R.O., Dever, D.P. and Porteus, M.H., 2018. CRISPR/Cas9 genome editing in human hematopoietic stem cells. Nature protocols, 13(2), pp.358-376.
Cullot, G., Boutin, J., Toutain, J., Prat, F., Pennamen, P., Rooryck, C., Teichmann, M., Rousseau, E., Lamrissi-Garcia, I., Guyonnet-Duperat, V. and Bibeyran, A., 2019. CRISPR-Cas9 genome editing induces megabase-scale chromosomal truncations. Nature communications, 10(1), pp.1-14.
Gribben, R., 2019.The controversy over gene-editing. Available at: http://www.pharmatimes.com/web_exclusives/the_controversy_over_gene-editing_1274582 (Accessed: 7 October 2021).
Haapaniemi, E., Botla, S., Persson, J., Schmierer, B. and Taipale, J., 2018. CRISPR–Cas9 genome editing induces a p53-mediated DNA damage response. Nature medicine, 24(7), pp.927-930.
Liu, J., Chang, J., Jiang, Y., Meng, X., Sun, T., Mao, L., Xu, Q. and Wang, M., 2019. Fast and efficient CRISPR/Cas9 genome editing in vivo enabled by bioreducible lipid and messenger RNA nanoparticles. Science assignmentAdvanced Materials, 31(33), p.1902575. Mei, Y., Wang, Y., Chen, H., Sun, Z. and Ju, X., 2016. Recent Progress in CRISPR/Cas9 Technology. [online] www.researchgate.net. Available at: https://www.researchgate.net/publication/291185471_Recent_progress_in_CRISPRCas9_technology (Accessed 7 October 2021).
Moro, D., Byrne, M., Kennedy, M., Campbell, S., and Tizard, M., 2021. Daneshyari.com. Available at: https://daneshyari.com/article/preview/8846245.pdf (Accessed: 7 October 2021).
Ran, F. A., Hsu, P. D., Wright, J., Agarwala, V., Scott, D. A. and Zhang, F., 2013. "Genome engineering using the CRISPR-Cas9 system", Nature Protocols, 8(11), pp. 2281-2308.doi: 10.1038/nprot.2013.143. Available at: https://www.nature.com/articles/nprot.2013.143 (Accessed: 7 October 2021).
Rosenblum, D., Gutkin, A., Kedmi, R., Ramishetti, S., Veiga, N., Jacobi, A.M., Schubert, M.S., Friedmann-Morvinski, D., Cohen, Z.R., Behlke, M.A. and Lieberman, J., 2020. CRISPR-Cas9 genome editing using targeted lipid nanoparticles for cancer therapy. Science advances, 6(47), p.eabc9450.
Song, R., Zhai, Q., Sun, L., Huang, E., Zhang, Y., Zhu, Y., Guo, Q., Tian, Y., Zhao, B. and Lu, H., 2019. CRISPR/Cas9 genome editing technology in filamentous fungi: progress and perspective. Applied microbiology and biotechnology, 103(17), pp.6919-6932.
Zhan, T., Rindtorff, N., Betge, J., Ebert, M. P. and Boutros, M., 2019."CRISPR/Cas9 for cancer research and therapy", Seminars in Cancer Biology, 55, pp. 106-119.doi: 10.1016/j.semcancer.2018.04.001. Available at: https://www.sciencedirect.com/science/article/pii/S1044579X17302742(Accessed 7 October 2021).