Good to Know

What is Gene Editing?

Gene Editing - DNA with scissors

The next frontier for medicine, cell and gene therapy, is designed to treat disease at its source by making changes to the body’s basic set of instructions or restoring the body’s functionality by replacing damaged tissue. One groundbreaking area of focus is gene editing, a technique that allows scientists to, for example, correct faulty genes that cause a specific disease, thereby aiming to reverse certain disease symptoms or prevent the disease from occurring in the first place.

2:23 | Jun 21, 2022

A Delicate Editing Tool for DNA 

Gene editing encompasses many different tools and technologies, but the end-goal is the same: to address the root cause of a disease instead of managing its outcome, i.e., the symptoms. Changing genes outside of the body (ex vivo) involves modifying cells - either from the patient or from a donor - to correct genetic mutations or provide new functionalities, and then transplanting them into the patient.1 In vivo gene editing involves the modification of genes in cells while they are inside the body.1 This is a rapidly evolving field utilizing different technologies. The most widely used approach acts like a pair of “molecular scissors” enabling scientists to cut the DNA sequence at a specific spot and then correct, replace, or remove the faulty pieces of DNA.


Gene editing: A biomedical “swiss army knife”

Our DNA is comparable to the world’s biggest code book, containing words made up only of four basic letters – A (adenosine), C (cytosine), G (guanine), and T (thymine) – which, arranged correctly, provide instructions for making proteins.2 The DNA double helix in humans consists of three billion specific arrangements of these letters, and a single “typo” in that sequence can often be the cause for one of the more than 4,000 rare, monogenic, sometimes life-threatening diseases.3 


CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) is an efficient and versatile cutting-edge gene editing tool. By finding a specific stretch of DNA inside a cell, binding to it, and then precisely cutting the DNA at a defined location, it can induce the desired DNA sequence changes in the cell. This is why some scientists liken the technology to a “find and replace” or “backspace key” - capable of editing a single letter in a long genetic sequence. Other gene editing technologies are able to increase or decrease gene expression, install or remove DNA sequences, or switch specific genes on or off. That’s why gene editing could be compared to a “swiss army knife” with multiple tools that can perform different tasks. 


From Research Lab to Real World Use

Successful gene editing strategies may one day effectively halt or even reverse some of the most devastating genetic diseases such as sickle-cell disease, or beta thalassemia. In the future, this might expand even to other complex conditions. 


For example, CRISPR is already used in research labs around the world to produce modified cells and activate or turn off genes to better understand the mechanisms of disease, and many other applications in medicine are possible.4 Furthermore, in the pursuit of new cancer therapies, CRISPR has also become a methodology used in many oncology biology studies to correct some of the changes in DNA that are known to cause cancer or to arm immune cells with the right tools to effectively fight the cancer.5 


Modifying dysfunctional DNA offers new possibilities to combat some of humanity’s most difficult-to-solve problems. It has an unimaginable potential to change the world for the better by addressing diseases that currently have limited or no treatment options. That’s why we at Bayer are investing in gene editing technologies for the development of the next generation of medicines. 



1 American Society of Cell + Gene Therapy. Gene and Cell Therapy FAQs. Viewed November 18, 2021.
2 National Institutes of Health. National Human Genome Research Institute. Genetic Code. Viewed November 18, 2021.
3 Ehrhart et al. (2021) in Scientific Data
4 Leopoldina. Genome Editing/Potential Applications. Viewed November 18, 2021.
5 National Cancer Institute. How CRISPR Is Changing Cancer Research and Treatment. July 27, 2020. Viewed November 18, 2021.

5 min read