A Brief Introduction To Genome Editing

By Ranjana Jain, Research Nester

It has been estimated that within the next decade, genomics research will generate about 40 exabytes of data. In fact, the genome editing market and the rising interest in genomic research provides a pool of opportunities and offers a wide scope for growth. In this article, we discuss the various aspects of gene editing, including its pros, cons, and future aspects.

The Human Genome Project (HGP), which was carried out between Oct. 1, 1990, and April 14, 2003, recognized 3.1 million base pairs in the human genome. The National Human Genome Research Institute (NHGRI) discovered that genome sequences have changed significantly over 250,000 years of our species’ expansion. Moreover, it also found that around 80% of the ancestry populations that were included in large-scale genomic studies were of European populations, so the project was missing essential elements of human diversity. As a result, the NHGRI funded the Human Pangenome Reference Program to address these limitations.

Human DNA sequences are identical in over 99.9% of people, and the 0.1% genomic differences come from variations among the 3 billion bases that are present in our DNA. The variations in this 0.1% provide the chance of developing a disease.

With growing interest in genomic research, as well as the rising concern about chronic diseases globally, the need for genome editing for custom health therapies is on the rise.

Genome editing technologies enable removal, addition, or alteration of genetic material at particular locations in the genome. It is helpful in correcting genetic defects, preventing the spread of diseases, or even improving crops. Using CRISPR, scientists have developed precise Cas9 proteins and are able to achieve an accuracy level of over 99.9% for that particular gene modification.

The process of gene editing is divided into three categories: SDN1, SDN2, and SDN3.

• SDN1 involves editing the host genome DNA. This editing is done by using small deletions or insertions of the DNA, without introducing any other foreign genetic material.
• SDN2 editing involves the use of a small DNA template to generate specific changes.
• The SDN3 process involves a larger element of DNA. It may also include the full-length genes of foreign origin, which makes it very similar to genetically modified organism (GMO) development.

Applications of Gene Editing

1. Animal models: CRISPR-Cas9 can be utilized to fabricate animal models to imitate human diseases and impede the development of the disease by silencing or mutating the disease-causing gene.
2. Multiple gene mutations: CRISPR-Cas9 can be utilized to develop mutants for the target genes.
3. Genome editing in specific tissues: Scientists have been able to transform the genomes of specific tissues of various organs such as the brain and liver by using adeno-related viruses and hydrodynamic injection.
4. Treatment of diseases: CRISPR-Cas9 can be applied ex vivo or vivo. In the ex vivo approach, first the cells are removed from the body, then the CRISPR is registered to the cells and transferred back to the body. In the in vivo approach, CRISPR is directly applied to the cells in the body itself using non-viral and viral methods.
5. Biological military applications: These studies are usually focused on increasing the tolerance of soldiers to chemical or biological warfare. CRISPR has the capability to influence the performance optimization of humans.
6. RNA editing: ssRNA (single-stranded RNA sequences) can also be edited using CRISPR technology.

Some applications of CRISPR outside of human gene therapy development include making allergy-free food, developing yogurt and cheese resistant to viral infections, decaffeinating coffee beans, making greener fuels, and breeding faster racehorses.

Future Outlook for Genome Editing

Some of the notable companies in the gene editing field are Thermo Fisher Scientific, Intellia Therapeutics, Horizon Discovery Group, Sangamo Therapeutics, Editas Medicine, Inscripta, and Inari Agriculture. The genome editing market is expected to garner $13 billion by 2030, growing from a revenue of about $5.2 billion in 2021. The market is expected to grow due to rising government funding and growth in the number of projects based on genomics.