Analysis: SCOTT MATAFWALI
GENETIC engineering, also known as genetic modification or gene editing, has been a topic of varying contention for years and a negative connotation in Zambia. Recently, though, there has been a new fuel thrown on the fire worldwide with the discovery of the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technique.
Genetic engineering can be defined as the process of introducing an insertion, deletion or replacement of DNA at a specific site of the cell or organism genome. This is usually engineered using nucleases known as molecular scissors.
Examples of programmable genetic engineering tools include Zinc Finger Nucleases (ZFNs), Transcription Activator-Like Effector-based Nucleases (TALEN) and CRISPR/Cas system.
The earlier engineered methods for targeting double-stranded breaks come with a lot of disadvantages. In 2012, Doudna and her colleagues developed a CRISPR-associated protein Cas9 nuclease technology based on a bacterial system from Streptococcus pyogenes. This technology revolutionised the way gene editing has been done because it is largely distinguished by its relative ease and great efficiency in both eukaryotic and prokaryotic cells.
Gene editing using CRISPR-Cas system may transform not just research and human disease, but our entire world.
Many sectors of life have been transformed, which include research, industrial and health sectors.
Medicine and agriculture make use of the gene editing techniques the most. Once thought incurable diseases like cancer and HIV have the potential to be cured using gene editing. It was by genetic engineering techniques that the first human insulin was developed for the diabetic patients.
In therapy, CRISPR has the potential to affect multiple therapeutic areas and many diseases, both rare and common.
The technology allows scientists to target the underlying cause of a disease and possibly cure it by modifying the patient’s genome. Some long-term applications are extremely exciting, such as in regenerative medicine. Recently, scientists in the United States have used CRISPR to shut down HIV replication and eliminate the virus from animal cells and laboratory mice.
This is very promising in the quest to finding the cure for the virus. Scientists are also engineering mosquitos and applying the gene drive technique in malaria, mutant mosquitos are created that will be resistant to parasites that cause malaria. The mosquitos will then spread the gene through wild population.
Many heart and autoimmune diseases have been treated by using gene therapy. In future, there is a possibility that gene therapy would be used to treat diseases such as Huntington’s disease or cystic fibrosis by replacing the defective genes with healthy ones or altering them.
Genetic engineering has enabled the pharmaceutical industries to make drugs that fight against disease efficiently.
For example, CRISPR-Cas9 can be applied in drug discovery allowing scientists to rapidly and efficiently screen for the activity of various genes or functional domains of proteins.
The screening of compounds usually takes a long time and is strenuous with only a handful of potentially therapeutic molecules emerging from thousands.
This technology can quicken that process and improve specificity.
In agriculture, CRISPR systems have been used to improve certain crops, allow some crops to grow in difficult conditions, resist disease and improve the shelf life of certain products like vegetables.
Approaches based on CRISPR-Cas9 have been used to modify the genomes of crop plants, farm animals, and laboratory model organisms.
Scientists have also succeeded in engineering the process (photosynthesis) to make it more efficient. Techniques like CRISPR are being used to engineer plants to grow in drought-prone areas with experiments underway in East Africa.
Although the gene editing tools like CRISPR-cas9 systems are very useful, there have been some issues that still need to be addressed such as off-target effects and unnecessary chromosomal translocations that could be disastrous.
More studies and effort are needed to improve the systems to create the next generation versions of gene editing tools.
There are also ethical and social implications surrounding the genetic engineering of human cells, raising concern to its applications such as biohacking and the possibilities of designer babies.
The ability to create genetic modifications on organisms easily raises profound questions on many aspects, the science involved, and even our ability to change the character world and all of Mankind.
Just as there was a rush to condemn invitro fertilisation and cloning, there has been a rush to condemn gene editing in general, despite its proven results and vast potential.
The author is a pharmacist and staff development fellow at the Copperbelt University.
Analysis: SCOTT MATAFWALI