Introduction

Selective breeding of plants and animals began 10,000 years ago, with crops such as wheat and barley. Early efforts in selective breeding focused primarily on improving crops for food production. Over time, the focus expanded to enhance desirable traits in animals as well. With advances in genetics and biology, selective breeding became increasingly sophisticated and effective for both plant and animal improvement. Today, technological advances have made gene editing (also known as genome editing) far more precise than traditional breeding techniques.  

Unlike traditional selective breeding, which can unintentionally impact multiple traits, gene editing allows scientists to target specific traits, such as disease resistance or drought tolerance, while minimizing unintended changes. This technology promises improvements in both agriculture and human health, among other areas. 

One of the most significant innovations in gene editing is Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technology, which acts like molecular scissors, enabling highly customized changes to DNA. Interestingly, CRISPR works like editing a letter or a few letters in a book, whereas selective breeding is more like changing entire paragraphs or chapters.  

This fact sheet will explain how gene editing works, why it’s effective, and how it can benefit farmers as well as those interested in this cutting-edge technology. 

How Gene Editing Works

The study of deoxyribonucleic acid (DNA) began in 1869; the double helix structure was discovered in 1953. This discovery set the stage for new ways to improve plant and animal traits. While the basic goals of gene editing are similar to those of traditional breeding, gene editing technologies offer greater precision and speed. 

Traditional breeding involves selecting plants or animals with desirable traits and crossbreeding them over multiple generations to enhance those traits while gradually eliminating undesirable ones. This process can take decades. In contrast, gene editing allows scientists to improve specific traits within a few years, significantly accelerating progress. 

Before conducting experiments, scientists must obtain approval from institutional oversight committees. In the United States, the release of gene-edited plants into the environment may also fall under the oversight of federal agencies such as the United States Department of Agriculture (USDA), the Environmental Protection Agency (EPA), or the Food and Drug Administration (FDA), depending on the characteristics of the modification.  

However, gene-edited plants that do not contain foreign DNA, and mimic changes possible through conventional breeding, are often exempt from extensive federal regulation, particularly under USDA guidelines.  

Applications of Gene Editing

Gene editing has broad applications across agriculture, aquaculture, human and veterinary medicine, and environmental sustainability. In agriculture, gene editing can improve crops and farm animals by making them more disease-resistant, enhancing nutritional value, increasing yields, and promoting climate resilience. 

An example of this is related to the growing global human population and limited freshwater resources, where water conservation in agriculture is critical. CRISPR technology may be used to edit crop plants, enhancing their ability to use water efficiently, tolerate salt, and withstand drought. This can help mitigate challenges related to limited arable land and water availability. From an environmental perspective, gene editing provides the potential to reduce the need for pesticides, promote sustainable farming practices, and contribute to the restoration of endangered species and ecosystems. 

In animals, gene editing is being used to enhance disease resistance and growth, while adhering to strict animal welfare guidelines. For example, gene editing technology created pigs that are resistant to porcine reproductive and respiratory syndrome, improving their health.  In human health, gene editing offers the potential for treating genetic disorders, and ongoing research could lead to disease prevention in the future. An example is the clinical trial using CRISPR gene editing in patients with sickle cell disease to alleviate symptoms. 

Common Concerns with Gene Editing

Like any technology, gene editing comes with both benefits and challenges. Among the concerns are off-target effects, gene transfer to other plants, environmental impacts, efficiency, and ethical considerations. 

Off-target effects may occur when gene editing tools modify DNA sequences at unintended locations, potentially causing undesired changes in the organism. Researchers are actively working to minimize these effects by improving editing techniques, and using advanced DNA sequencing to detect and correct such changes.  

Another concern is the potential transfer of edited genes, where modified plants might cross-pollinate with wild relatives. The concern includes negative impacts on biodiversity and ecosystem stability. One approach to mitigating this risk is the development of sterile plants, a strategy useful for vegetatively propagated species, where seed production is not needed.  

Finally, social and ethical concerns arise as technology evolves. However, existing and new regulations are being implemented to ensure that gene editing benefits society and does not lead to unintended consequences. 

The Future of Gene Editing

Gene editing is revolutionizing agriculture, medicine, and sustainability. In agriculture, it holds the potential to create crops that are more resilient to drought, pests, and diseases. These are critical advantages for farmers dealing with extreme weather and shrinking farmland. Gene editing can also help produce food with a better shelf life, more nutrients, and human health benefits. It can also be more efficient with a smaller environmental footprint, supporting long-term sustainability. 

In medicine, gene editing offers the possibility of treating genetic disorders and improving human health. As technology progresses, scientists and industry leaders are working to balance innovation with responsibility, ensuring that gene editing is safe, ethical, and beneficial for people, farmers, and communities worldwide. 

By embracing this powerful tool, we can enhance food production, advance medical treatments, and promote sustainability, all while ensuring the responsible use of technology for future generations.  

Resources

• Gene Editing and Plant Protection 

• Identifying New Frontiers in Gene Editing 

• Technologies in Plant Breeding 

• The Future of GMOs 

• The Regulation Process 

Ahmad, A., Munawar, N., Khan, Z., Qusmani, A. T., Khan, S. H., Jamil, A., ... & Qari, S. H. (2021). An outlook on global regulatory landscape for genome-edited crops. International Journal of Molecular Sciences, 22(21), 11753. 

Chen, L., Li, W., Katin-Grazzini, L., Ding, J., Gu, X., Li, Y., ... & Li, Y. (2018). A method for the production and expedient screening of CRISPR/Cas9-mediated non-transgenic mutant plants. Horticulture Research, 5.  

Clark, L. F., & Hobbs, J. E. (2024). What Is Gene Editing?. In International Regulation of Gene Editing Technologies in Crops: Current Status and Future Trends (pp. 15-29). Cham: Springer Nature Switzerland. 

Farinati, S., Draga, S., Betto, A., Palumbo, F., Vannozzi, A., Lucchin, M., & Barcaccia, G. (2023). Current insights and advances into plant male sterility: new precision breeding technology based on genome editing applications. Frontiers in Plant Science, 14, 1223861. 

Grieger, K., Loschin, N., Barnhill, K., & Gould, F. (2024). Let’s talk about genetic engineering: A guide to understanding genetic engineering and its applications in food, agriculture, and the environment. NC State Extension Publications. https://content.ces.ncsu.edu/lets-talk-about-genetic-engineering 

Kumar, R., Kamuda, T., Budhathoki, R., Tang, D., Yer, H., Zhao, Y., & Li, Y. (2022). Agrobacterium-and a single Cas9-sgRNA transcript system-mediated high efficiency gene editing in perennial ryegrass. Frontiers in Genome Editing, 4, 960414. 

Liu, Y., Chen, Z., Zhang, C., Guo, J., Liu, Q., Yin, Y., ... & Liu, X. (2024). Gene editing of ZmGA20ox3 improves plant architecture and drought tolerance in maize. Plant Cell Reports, 43(1), 18. 

Luo, K., Duan, H., Zhao, D., Zheng, X., Deng, W., Chen, Y., ... & Li, Y. (2007). ‘GM‐gene‐deletor’: fused loxP‐FRT recognition sequences dramatically improve the efficiency of FLP or CRE recombinase on transgene excision from pollen and seed of tobacco plants. Plant Biotechnology Journal, 5(2), 263-374. 

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