Genetic disorders have plagued humanity for ages, impacting individuals with inherited or acquired conditions. Over the years, extensive research has been devoted to gene editing, and recently, the groundbreaking CRISPR gene editing technique has shown remarkable potential. One notable success story is that of Victoria Gray, who underwent CRISPR treatment for sickle cell disorder.,
Crispr was first discovered in 1987, and the reserchers that found it didn't even understand what they found. They were investigating a gene in E.coli when they noticed an interesting pattern in the sorrounding of the DNA which was made up of 5 identical repeating sequences made up of 29 bases, which was separated by 32 base blocks of spacer DNA. Over the years, researchers were able to find the sequences in other microbes., and was refered to as Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR). This repeats were next to certain enzyme-producing genes known as Crispr Associated Genes (CAS) and they were able to cut the genes.,
Over time, CRISPR was understood, and people started to understand them as weapons bacteria were using against viruses. If a virus infects a bacteria, it injects its genome into the cell. A new spacer is derived from the viruses genome in the case of a new virus and incoporated into the virus genome. The spacers are histories of old viral infection, giving the bacteria immunity against the virus in the future. The sequence of the CRISPR is then transcribed to create RNA molecules which then binds with with the matching DNA which then causes the CAS to cut and destroy the invading genome from the sequence causing the virus to die as a result of not being able to replicate. ,
Capitalizing on this bacterial defense, scientists aimed to employ CRISPR for editing human genes. Unlike previous DNA-cutting techniques using restriction enzymes, CRISPR-CAS9 allows for precise cuts at specific locations in the genome.
With CRISPR gene editing, genetic materials can be removed, added, or altered within a particular location in the genome. To be able to use CRISPR in the lab, a short guide RNA sequence is synthesized which matches the sequence of the gene to be edited, then the guide RNA carries the CAS9 enzyme to the place where the editing is to be done and makes a cut in the exact location. When this cut is done, the DNA is damaged, and the cell DNA repair machinery starts to repair the damage thereby removing the damaged one. Also, scientists could add customized DNA sequences to the gene to help replace and repair the genetic sequence.
Following Gray's genetic editing experience, she has experienced great changes and has been able to produce more fetal hemoglobin and her bone marrow cells contain the modification needed to produce fetal hemoglobin., Asides from Gray, patients who suffer from Beta Thalassemia have also received CTX001 which would help them restore fetal hemoglobin production in their bone marrows.,
While this isn't a major cure for now, it is not yet fully solving a lot of genetic problems, and it is still expensive to perform. Also, while Crispr is making the papers and scientists are talking about it in conferences and meetings, a lot of things still need to be checked like its potential downsides, the lifespan of the treatment if CRISPR is used to edit genes, is it safe in the long term and so on.
Scientists are exploring its potential in reversing conditions like Cystic Fibrosis, Cancer, Genetic Blindness, Muscular Dystrophy, and more. It is no doubt that CRISPR gene editing offers hope for addressing genetic disorders, but there is still much to explore and refine before it becomes a widespread and accessible solution to various genetic challenges.
