You have probably read stories about a new study using the CRISPR genetic modification – a technique also called Cas9. As it is cheaper, simpler and more efficient than other approaches for changing DNA, the world is convinced with this technology. The term CRSPR-Cas9 stands for ‘Clustered Regularly Interspaced Short Palindromic Repeats-CRISPR-associated protein 9. The names reflect tributes but don’t tell us much about how it functions, before anyone understood what is was, since they were coined.
IS CRISPR THE GAME CHANGER?
Doctors have infused cells edited using CRISPR-Cas9 into two patients in a trial conducted at the University of Pennsylvania, NPR reports today (April 16 2019)
What’s CRISPR and how does it work? What does CRISPR-Cas9 do?
CRISPR-Cas9 is a process used to alter the genetic makeup of organisms allowing scientists to proficiently insert or delete precise bits of DNA with exceptional accuracy.
CRISPR-Cas9 is a system found in bacteria and involved in immune defense. Bacteria use CRISPR-Cas9, an enzyme, to cut up the DNA of invading bacteria viruses that might otherwise kill them. Today we have adapted this mechanism to change any letter that was chosen. We might want to fix a disease or error that crept or was inherited into our DNA when it replicated. Or, in many cases, we may want to enhance crops, livestock or maybe people’s code.
So, do we replace it and snip the gene that is undesirable out?
We must remember that plants and animals are composed of millions of cells, and also each cell includes the same DNA. There’s no point editing just one cell: we’d have to edit the exact same gene in every cell. We’d have to snip out millions of genes and also paste in millions of new ones. And not all cells are simple to get to. How could we reach cells buried within our bones or deep inside a brain? A much better approach is to begin at the beginning and edit the genome while there’s just one cell – a very early embryo. Therefore, all we need is a giant microscope and also a tiny pair of scissors. And that’s basically, what we use. Cas9 is the technical name for the virus destroying scissors which evolved in bacteria.
What’s in a name?
The CRISPR part of the name comes from repeated DNA sequence which were part of complex method telling the scissors that portion of the DNA to cut. Find, Cut and after that Paste – ln order to credit our Cas9 scissors we link them to an artificial guide that credits them to the corresponding segment of DNA. Remember DNA comes within two strands, with a single strand fitting alongside another. We create a guide with a code which will line up with just one portion of our 3 billion base pair long genome – it’s just like a Google search. Then our scissors could make the cut in precisely the right place. After the Cas9 scissors cut the DNA simply where we intend, the cell unit will attempt to fix the break with any available DNA it can find.
CRISPR – More than just editing!
CRISPR technology is a simple yet effective way to edit genomes. Diseases and other inherited illnesses may virtually be erased from genetics. It allows scientists to easily change DNA sequences and enhance gene use empowering wide-ranging applications, spanning from being a disease therapy to farming and animals. It also includes adjusting genetic flaws, processing and preventing the spread of diseases and improving crops.
Sticking out in a crowded field
CRISPR technology can help yield leaner meat, enhance infection resistance in livestock, eliminate allergens from milk and many others to benefit humans and animals. Engineering mosquitoes with gene editing has helped stop the spread of viruses such as malaria. Also, edits in mice helped reduce infections among humans because they could no longer pass on Lyme disease to ticks.
The primary focal point for CRISPR engineering is fixing genetic flaws, such as retinal illness, in humans. Gene editing has gained more muscle since there has been very little progress made by researchers while using other methods. With no cure available in the market, CRISPR is the only option.
Gene editing in pigs, in the future may be considered to help with organ transplants because it can provide tissues which might be less rejected by patient’s body.
CRISPR technology would assist us in the battle against AIDS in some ways. CRISPR can be utilized to get the HIV virus out of the DNA of resistant cells. The other way would be to alter the system so that the virus is no longer able to attach the structure making us impervious to HIV infections.
Somatic gene editing can help scientists treat diseases like sickle cell disease triggered from single mutated gene by editing the cells in the affected tissues of the patient either outside or within the body.
CRISPR engineering is very easy to apply and inexpensive unlike the complicated TALENS i.e. Transcription activators-like effective nucleases. Since the method is very simple, it can be used to perform tumor associated chromosomal translocations precisely. The technique can be useful in many fields such as brain tumors and other diseases.
One of these greatest components of CRISPR is its ease-of-use. The novice person will be up-and-running with this technology in no time. These sequences for these CRISPR-associated proteins, including Cas9 and Cpf1, may be prearranged from the DNA manufacturing company (IDT, GeneArt and more) or mandated as the pre-made DNA sequence (Addgene).
As revolutionary as CRISPR has existed for biomedical science, its breakthrough stemmed from fundamental scientific curiosity about the life issues. With CRISPR, today we can point virtually any factor with higher efficiency. Deliberating about CRISPR today is of high importance because this field is on this cusp of usage on humans, including human embryos.
Designer Babies – A cause of concern?
The most debated research involves the germline gene editing where the sperm, eggs and early stage embryos are altered to shield the child from inherited diseases such as Alzheimer’s, Cancer and Diabetes. This process though, can possibly be misused to select certain physical traits or enhance human performance resulting in designer babies with the capacity to pass on the traits to the offspring. There are demands to have an international ban on producing genetically engineered babies as it brings risk of aggravating social inequality by giving an advantage to parents who can afford it. The claim is that intervention should be permitted only if it is a medical necessity. They contend that it transcends the limits of human safety and needs more research and observation keeping in mind the safety and permission from the future generations.
Harnessing the future of CRISPR – Business gains or human well-being?
The ability to change DNA is for sure altering the source code of life. The technology is still new, and its effect on future generations is unknown and uncertain. Scientists are also at an early stage of figuring out how well we utilize CRISPR to change this world for the greater. Eventually, new devices and technologies, such as CRISPR, and reduced value of genomic sequencing can revolutionize the care system and can dramatically decrease the average cost of care by focusing on prevention rather than treatment, medicine and administration.
However, its commitment also raises moral concerns. The potential of experimenting with something that powerful, with possible results that will be passed on to generations is terrifying to some. CRISPR explorations and research must remain made responsibly and ethically. The ethical propositions of editing are not about the process but related to the purpose for which it is being used.
With volumes of these capacities CRISPR appears to take, who would remain in charge of making sure that we do not get too far, but still fight the obstacles that fall to keep these technologies from achieving their full potential?