OVERVIEW
This week we learnt about central dogma of gene expression: “one gene–one protein” hypothesis, which means one Gene makes one protein (Polypeptide). This is two-step process, in the first step genetic code stored in DNA transcribed into RNA. In the second steps message transcribed in RNA is translated into amino acids by Ribosomes. The rules for translation of the coded message into amino acids are contained in the genetic code. This chain of events is full of glitches in the form of errors in both the incorporation of nucleotides into RNA and amino acid incorporation in proteins. Errors in protein synthesis disrupt cellular fitness, cause disease phenotypes, and shape gene and genome evolution. Gene editing may help to repair errors.undefined
The 2020 Nobel Prize in Chemistry has gone to Emmanuelle Charpentier and Jennifer A. Doudna “for the development of a method for genome editing.” That method, formally known as CRISPR-Cas9 gene editing but often called simply CRISPR, allows scientists to precisely cut any strand of DNA they wish and repair it. Thus, the new gene-editing tool CRISPR — can make heritable changes in human embryos. Good part of CRISPR is that it may give us the cure to HIV, genetic diseases, and some cancers, and will help address the world’s hunger crisis. Yet even the most minuscule changes to DNA could have numerous unexpected ethical and societal consequences and may even have unimaginable power to control evolution.
Watch the video and read the suggested reference to answer the following questions:
- What does CRISPR stand for?
- Which type of organism’s harbor/contain this system? And what is the CRISPR-Cas9 system function in those organisms?
- For medical applications, provide a guide how the CRISPR-Cas9 can be used to fix gene errors in cystic fibrosis or any other genetic disorders. (use the video and reference listed below).
- Basic mechanism of evolution is gene mutation. Discuss how CRISPR can control evolution process?
- Gene editing using CRISPR-Cas9 is not without ethical dilemma, can you provide an example where the clinical application of CRISPR-Cas9 can lead to ethical issues? Provide one example.
Suggested references for this discussion:
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4403038/
- https://www.scientificamerican.com/custom-media/biggest-questions-in-science/the-long-view-on-gene-editing/
- https://youtu.be/MnYppmstxIs
- https://www.youtube.com/watch?v=MnYppmstxIs