Molecular biology tool CRISPR/Cas9 nailing new era of technology
November 6th, 2017 | Najam-us-Sahar Durrani | No Comments
With the advancement of technology, therapeutics have also entered a new era with emerging technology of the time that is biotechnology and genetic engineering. Many of the diseases like sickle cell anemia can be cured using genetic manipulation approach but there are some constraints technologically that has made the therapeutic gene editing insufficient to be a therapy.
Some of the problems along with most expensive and ethical issues relating to so far discovered systems for gene therapy is it’s not target specific that is the gene added can be bind to some other regulator of a gene can give rise to another challenge in therapy. Being not target specific it was a therapy to go for when you have a situation like do or die. Only in such conditions, it can be tried.
The discovery in 2013 by Feng Zhang opened a new window for genome editing at the level of therapeutic possibility. In his research, he engineered an innovative version of CRISPR-Cas9 to edit human genomes. CRISPR-Cas9 is a remarkable leap in research in terms of speed and efficiency.
Feng Zhang and Nobel laureate Phillip Sharp successfully engineered a mice model using CRISPR-Cas9 to model deadly effects of mutations in cancer. The ability of their system to introduce loss of function mutations in tumor suppressor genes and gain of function in proto-oncogenes facilitate screening of causal genetic mutations.
After the series of experiments, CRISPR/Cas9 has been chosen as the preferred method for genome editing due to its high degree of fidelity, relatively simple construction and low cost.
CRISPR/Cas9 have immense therapeutic value so far at research level it had successfully cured deadly blood disorder like thalassemia. There were also some studies revealing the possibilities to completely eradicate the notorious HIV/AIDS and other genetic disorders like cancers. Clinical trials have found effective in curing cancers.
Now to look what exactly is CRISPR and how it works let’s have a look at the biology of CRISPR/Cas9.
CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats. Initially, CRISPRs were identified as segments short, palindromic repeat base sequences of prokaryotic DNA. Short segments of spacer DNA of prior exposures to foreign DNA (e.g., a virus or plasmid) are right beside palindromic sequence. CRISPR-associated system that consists of Small clusters of cas genes is positioned next to CRISPR sequences.
Cas9 nuclease complexed with a synthetic guide RNA (gRNA) when guided into a cell. The cell’s genome can be cut at a desired site either to remove or develop additional ones. A naive version of the CRISPR/Cas system, CRISPR/Cas9 that has been adapted to edit genomes.
CRISPR/Cas genome-editing techniques are applied in medicine and crop seed enhancement. Use of CRISPR/Cas9-gRNA complex for genome-editing was the American Association for Advancement of Science’s innovation in 2015. The rapid progress in developing Cas9 into a set of tools for cell and molecular biology research as high efficiency and versatility of the system. CRISPR/Cas system of the designer nuclease systems currently available for accurate genome engineering. Cas9’s potential usefulness for genome specific enlistment of proteins will be restricted only by our imagination just needed more efforts for revelation.
This new genome editing technology is a cautionary tale. We can easily get caught up in the glamour of scientific and technological advancement while at the same time oblivious to the ethical ramification of such scientific and technological advancement. Several bioethical concerns have been dealt with using CRISPR for germline editing.
Although the science of genomic holds some promises like personalized medicine, human genetic modification and the development of new drugs to help the sufferings of mankind, its deadly effect is it can disturb the natural ecology that is disturbing the natural balance. Discovery of CRISPR/cas9 revives many other social and ethical issues, not only with humans, also with other organisms and the environment, such as considering the non-maleficence principle in risk assessment, safety issues to avoid ecological impairment or the possible use of the technique for genetic enhancement.
Despite the constraints, the positive impacts cannot be neglected the only need is to devise a mechanism that Scientist can use to benefit mankind and lessen his sufferings. Public, religious scholars, academics, researcher and the governments together have to work in these aspects taking this technological tale to next level of making impossible possible.
Short Link: https://www.technologytimes.pk/?p=19099