Introduction

RNA interference (RNAi) is a natural process used by cells to regulate genes and turn them on or off. It has become more widely used in the therapeutics world, as further experimentation and research has been done, and as more FDA approved drugs are being approved. RNAi can be used by prokaryotic organisms (bacteria and archaea) and eukaryotic organisms (animals, plants, fungi). Eukaryotic cells mostly use this mechanism to defend themselves against viruses, maintain the genome integrity and regulate gene expression in the cell. Essentially, RNAi is a process that uses outside (not from the host or lab made) RNA to block out/silence the cell’s own RNA, before the cell can make proteins, which causes the phenotype to be different than its wild type one. (Kim & Rossi, 2008; Thermo Fisher Scientific, n.d.).

The central dogma in biology is the process of taking DNA, a double stranded molecule, and replicating it to have two copies of the exact same molecule. This replicated DNA is then transcribed into mRNA (messenger RNA), which carries the code to translate the mRNA to proteins. The mRNA nucleotides are grouped into codons, 3 base pairs, and coded into an amino acid, which is a functional protein that is essential for life and metabolic function. These amino acids can be linked together to make polypeptide chains, which make up the proteins. These polypeptide chains, depending on the type of amino acid sequence that it is made of, are going to be what gives the protein a specific structure and function, contributing to the phenotype of a specific organism. A change in the genetic information from the DNA in the beginning of the process can directly impact the type of protein that is coded, and therefore will change the phenotype that is expressed. (Kim & Rossi, 2008; Thermo Fisher Scientific, n.d.).

RNA is a small, single, flexible, stranded nucleic acid that can form secondary structures with itself. Forms of RNA include: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA), which are all used in the process of gene regulation and protein synthesis. Double stranded RNA (dsRNA) is a form of RNA that is usually found in viruses, can come from transposons, be introduced experimentally, and be used in the form of silencing gene expression. dsRNA is in the shape of a helix and is more structurally rigid than single stranded RNA. dsRNA is used to initiate RNA interference. The mechanistic process of RNA interference is complex, as seen directly in Image 1. dsRNA can be chopped up into smaller RNA molecules, roughly 20-25 base pairs long. These chopped up RNA molecules are called small interfering RNAs (siRNAs). siRNAs direct the degradation of complementary messenger RNA (mRNA). If the mRNA is degraded then it can not be transcribed into a protein, and therefore, the gene will not be expressed. This is essentially silencing the gene phenotype, coining the name of “knocking” the gene down. siRNAs are produced by the cytoplasmic nuclease enzyme, Dicer. Dicer cleaves the dsRNA, creating siRNAs that unwind the helical RNA strand and are loaded into the RNA-induced silencing complex (RISC). Within RISC, the siRNA attached to the RNA strand is unwound. One strand is degraded, as it is not needed, while the other, which is the guide strand, remains attached to the RISC+siRNA complex. RISC includes a protein called the Argonaute protein that acts as molecular scissors and gene regulators. These proteins use the strands of RNA to guide it to the specific mRNA that needs to be cleaved to inhibit translation, and in turn gene expression. In humans, the argonaute protein used is Ago-2. This removes one strand of RNA and uses the remaining guide strand to recognize and cleave the target mRNA. Through this sequence-specific targeting, RNAi allows cells to regulate gene expression by silencing specific genes of interest with high precision (Kim & Rossi, 2008; Thermo Fisher Scientific, n.d.). For further clarification on the mechanistic process of RNA interference look below at video 1 as this depicts the mechanism in a visual clear way.

Image 1. The RNA interference (RNAi) process. Small interfering RNA (siRNA) enters the cell and becomes part of the RISC complex, where it guides the complex to a matching mRNA. The target mRNA is then cut and degraded, stopping the production of the corresponding protein. (OpenAI. (2026)). Note. Image generated using ChatGPT (DALL·E) by OpenAI, 2026.)

Video 1 Link: https://www.youtube.com/watch?v=UPSEMBgA3CI

Video 1. This video demonstrates how RNA interference (RNAi) works, showing how siRNA molecules target and break down specific mRNA to stop protein production, a process that can be used to treat certain diseases

Connection to sts

The interdependence of science, technology, and society is exemplified by RNA interference. From a scientific perspective, RNAi highlights how knowledge is often generated through the interpretation of unexpected results rather than through a strictly linear process of discovery. Early observations of gene silencing, such as cosuppression in plants and quelling in fungi, were initially confusing. However, through continued experimentation and reinterpretation, scientists were able to construct a new understanding of gene regulation. This demonstrates that scientific knowledge is not simply uncovered, but is shaped by human interpretation, collaboration, and evolving perspectives (Sen & Blau, 2006).

The development of RNAi also connects to the idea of social constructivism which shows that scientific knowledge is influenced by social processes and the context in which discoveries are made. In addition, RNAi illustrates path dependence, where early discoveries shape the direction of future research.  Once double-stranded RNA (dsRNA) was identified as the key trigger for gene silencing, research expanded into the study of small interfering RNAs (siRNAs), ultimately leading to the development of RNAi as a significant research tool and therapeutic strategy. This progression demonstrates how initial breakthroughs can establish a trajectory that guides future innovation while potentially limiting alternative approaches.

Technologies such as molecular cloning, genome sequencing and targeted drug delivery systems have made it possible to study and apply RNAi with high precision (Kara et al., 2022). Without these technological advancements, the practical applications of RNAi in medicine and research would not be possible. These technologies not only drive the advancements and further experimentation of RNAi, but without these technologies, the practical applications of RNAi in medicine and research would not be possible.

From a societal perspective, RNAi has had a significant impact on medicine, particularly in the development of targeted therapies for diseases such as cancer and genetic disorders (Traber & Yu, 2024). These therapies offer more precise treatment options compared to traditional approaches, contributing to the advancement of medicine. However, RNAi also raises important ethical and social considerations, mainly including issues of cost and accessibility. These challenges highlight the concept of missing voices, as not all populations have equal access to these emerging therapies. Overall, RNA interference demonstrates that science, technology, and society are deeply interconnected. Scientific discoveries drive technological innovation, while technology enables new forms of research, and both influence societal outcomes, including who benefits from advancements and who is excluded.

information

history and milestones

RNAi is a mechanism of gene regulation that was discovered through a series of unexpected experiments. In 1990, Napoli and Jorgensen first observed an RNAi-like phenomenon while studying petunias. When they introduced additional copies of a pigment-producing gene, instead of enhancing color, both the introduced and endogenous genes were silenced. An endogenous gene refers to a gene that is naturally present and expressed within an organism’s genome. With their discovery, they termed this phenomenon “cosuppression,” suggesting that the added gene was interfering with the expression of the plant’s native gene (Fire et al., 1998; Sen & Blau, 2006).

After the major breakthrough by Napoli and Jorgensen, similar individuals continued to observe mechanisms of gene-silencing effects. In fungi and animals, the process of “quelling” was discovered. This was both sense (the positive strand that is 5’-3’ and matches the original DNA coding strand) and antisense (the negative strand that is 3’-5’ and complementary to the DNA coding strand) RNA that unexpectedly triggered mRNA degradation. These findings challenged traditional ideas about gene regulation and suggested that RNA molecules could play an active role in controlling gene expression (Sen & Blau, 2006)

From further and thorough experimentation, a major breakthrough happened in 1998 when Fire and Mello published a paper that provided an explanation for the previously reported silencing of endogenous genes by “cosuppression, quelling and sense mRNA”. The scientists worked with C. elegans, and demonstrated that double-stranded RNA (dsRNA), rather than single-stranded RNA, was the key trigger of this silencing effect, establishing RNAi as a conserved and sequence-specific process (Sen & Blau, 2006). The significance of this work was recognized globally when Fire and Mello were awarded the 2006 Nobel Prize in Physiology or Medicine for their discovery of RNA interference (The Nobel Assembly, 2006). Following this breakthrough, rapid advances in molecular biology and biotechnology allowed researchers to better understand the underlying mechanisms of RNAi, including the roles of key components such as Dicer and the RNA-induced silencing complex (RISC) (Kim & Rossi, 2008).

Once its mechanism was understood, RNAi transitioned from simply a curious experiment to a powerful research tool and, eventually, a promising therapeutic strategy. It is now widely used in functional genomics to study gene function and has laid the foundation for the development of RNAi-based treatments targeting a wide range of diseases (Howard, 2013).

Therapeutic applications

Beyond its biological function, RNA interference (RNAi) has had a profound impact on society by transforming how diseases are studied and treated. When microRNAs (miRNAs) are not properly regulated, they can contribute to the development of diseases, including cancer, by affecting genes that control important cellular processes such as cell proliferation, apoptosis, and tumor progression. Tools such as miRNA mimics, anti-miRNAs (antagomirs), and small interfering RNAs (siRNAs) can specifically target and silence these disease-related genes through RNA interference (RNAi). This high level of precision makes them promising options for targeted therapies and personalized medicine (Chery, 2016; Liu et al., 2010). Unlike traditional treatments that often affect multiple pathways and can cause widespread side effects, RNAi-based therapeutics allow for highly specific silencing of disease-causing genes, making them especially valuable in the treatment of genetic disorders, cancers, and metabolic diseases (Kim & Rossi, 2008; Kara et al., 2022).

In addition to improving patient outcomes, RNAi has accelerated advancements in biomedical research and drug development. It enables researchers to rapidly study gene function by selectively “knocking down” genes, expanding our understanding of complex diseases and biological pathways (Howard, 2013). While research involving RNAi began in the 1990s, FDA-approved therapeutics did not emerge until 2018, with the first being Onpattro (patisiran). As of early 2026, six RNAi-based drugs have been approved: Onpattro (patisiran), Givlaari (givosiran), Oxlumo (lumasiran), Leqvio (inclisiran), Amvuttra (vutrisiran), and Rivfloza (nedosiran).

All but Givlaari were found to follow the common mechanism used by genome derived miRNAs in targeting the 3’ UTR. Givlaari interferes with the coding sequence of the target mRNA. Givlaari is used to treat acute hepatic porphyria (AHP), a genetic disorder affecting heme production. The most recent, Nedosiran, approved in 2023, targets the LDHA (lactate dehydrogenase A) gene and treats the primary hyperoxaluria disease, which results in recurrent kidney stones and a buildup of oxalate, in the kidneys. Lumasiran and Rivfloza work similarly to treat primary hyperoxaluria, a condition that also leads to excessive oxalate production and kidney damage. It can also lead to end-stage renal disease. Onpattro is a treatment for amyloidosis, which is a buildup of abnormal amyloid proteins in organs and tissues and leads to organ failure. Amvuttra is another treatment for hATTR amyloidosis, similar to Onpattro. Patisiran and vutrisiran are both indicated for the treatment of hereditary transthyretin-mediated amyloidosis (hATTR) a disease characterized by the buildup of amyloid fibrils in the liver caused by the unregulated aggregation of TTR. And lastly,  Leqvio is used to lower high cholesterol (LDL (lipoprotein) levels) in patients at risk for cardiovascular disease (Traber & Yu, 2024).

The discovery of RNAi-based gene silencing strategy provided a significant breakthrough not only to functional genomics research but also to targeted therapeutic applications for a broad range of pathologic conditions, including cancer. (Cherry, 2016). However, while RNAi offers significant benefits, its societal impact is also shaped by challenges such as high costs, accessibility, and the need for continued technological improvement (Traber & Yu, 2024). Overall, its ability to precisely regulate gene expression has not only advanced our understanding of disease mechanisms but has also opened new pathways for developing more effective and targeted treatments, ultimately improving healthcare outcomes and shaping the future of medicine. Outlined therapies, as depicted above, on how RNAi is used can be seen in Image 2 below.

Image 2: RNA interference (RNAi) in therapeutic applications. This figure highlights how RNAi is used to treat diseases by selectively silencing disease-causing genes. Examples of current applications include liver diseases, genetic disorders, and viral infections. FDA-approved RNAi therapies, such as patisiran, givosiran, and lumasiran, demonstrate the clinical use of this technology. The impact of RNAi includes high specificity, reduced side effects, and the development of new treatment options, contributing to advances in precision medicine.  (OpenAI. (2026)). Note. Image generated using ChatGPT (DALL·E) by OpenAI, 2026.)

challenges and limitations

While RNAi is a great method of creating new treatments for genetic disorders, there are a good amount of challenges and limitations faced in development. RNA is single stranded and therefore it is more easily susceptible to degradation by RNAses and is less stable than DNA (Kim & Rossi, 2008). The increased instability of RNA makes it more difficult to use therapeutically as this can lead to short levied in-vivo activity, rapid degradation or poor cellular delivery (Chery, 2016). In addition, RNAi molecules are often large or negatively charged, which can make it difficult for them to cross cell membranes and reach their intended targets without the use of specialized delivery systems (Kara et al., 2022). Another significant biological effect that is unintended is that RNAi therapies can trigger immune responses, or could bind other unintended targets and silence them unintentionally. These risks show the need for careful design and testing of the therapeutics to ensure both safety and specificity. Furthermore, as with many targeted therapies, there is the possibility that cells may develop resistance over time, reducing the long-term effectiveness of treatment (Kara et al., 2022; Kim & Rossi, 2008).

As previously mentioned, costs remain a major limitation. The cost to buy the RNAi products are extremely high, and therefore the cost to make and develop these products is also extremely high. This cost barrier limits the accessibility for many patients (Traber & Yu, 2024). Additionally, because these RNAi therapies are relatively new, there is still some uncertainty in regards to their long-term safety or the potential side effects. Continued research and clinical monitoring are still ongoing to fully understand the long-term impact and safety for patients. Overall, RNAi is a highly innovative and targeted approach to treating diseases, though these scientific, technological, and societal challenges must be addressed to ensure its safe, effective, and equitable use. Ongoing advancements in delivery systems, cost reduction, and clinical research will be essential for maximizing the potential of RNAi therapies in the future.

missing voices

A missing voice in the sphere of RNAi can be seen in the people who struggle with these genetic disorders, but lack the financial resources or access needed to get these FDA approved treatments. RNAi-based treatments are extremely expensive, often ranging from  $375,000 to over $1.6 million dollars, making them inaccessible for many individuals (Traber & Yu, 2024). As RNAi therapeutics continue to develop and expand in clinical use, challenges related to delivery, cost, and implementation remain significant barriers for access (Kara et al., 2022). Some manufacturers have programs that assist in payments, and insurance coverage, which can be a big help, but these are not always available and accessible for each individual. Alternative treatments, such as organ transplants or long-term chronic care, are also costly and may not be viable for patients without strong healthcare support systems. As a result this creates a notable gap in who is able to benefit from these advanced therapies.

Through time, hopefully these products will become more widely available to low income members of society, but for now, this is a missing voice that must be addressed. In order for this to be resolved, scientific and policy based solutions are required. A probable approach would be for the incorporation of more transparent and scaled pricing to expand the amount of people that can afford the treatments. Other potential solutions to this issue include expanded patient assistance programs and more inclusive clinical trials. (Traber & Yu, 2024) Ultimately, while RNAi represents a significant scientific advancement, it is equally important to consider who is able to access these therapies. By addressing issues of cost, accessibility, and inclusion, scientists, healthcare providers, and policymakers can work toward ensuring that the benefits of RNAi are more widely and equitably distributed.

conclusion

The discovery of RNAi is important to the field of Science and Technology Studies (STS) because it shows how scientific advancements are shaped by unexpected observations, technological advancements, and the way that scientists build on and interpret prior discoveries. RNAi has changed the way scientists study gene function by providing a faster and more precise way to silence genes, which has accelerated research in genetics, medicine, and biotechnology (Kim & Rossi, 2008; Howard, 2013). As explored in this chapter, RNAi has shown how biological mechanisms connect to drug development/clinical practice, while also highlighting ongoing challenges in stability, delivery, off-target effects, and ensuring equal access to life-changing therapies. These challenges emphasize that scientific progress is not solely a technical achievement, but also a societal one that requires careful consideration of accessibility, safety, and ethical implications. Moving forward, the continued advancement of RNAi will depend not only on innovations in science and technology, but also on efforts to ensure that its benefits are distributed fairly and responsibly. By addressing both the scientific and societal dimensions of RNAi, researchers and policymakers can help ensure that this powerful technology improves health outcomes while promoting greater equity in access to life-changing therapies.

Glossary

Ago-2 (Argonaute-2)
A specific Argonaute protein that cuts target mRNA during RNA interference.

Amino Acid
A small molecule that serves as a building block of proteins.

Antisense RNA
An RNA strand that is complementary to mRNA and can bind to it to block gene expression.

Argonaute
A protein in the RISC complex that helps recognize and cut target mRNA.

Codon
A sequence of three nucleotides in mRNA that codes for one amino acid.

Complementary
Refers to matching nucleotide sequences that bind together (A pairs with U, C pairs with G in RNA).

Cosuppression
An early observed gene-silencing phenomenon where both an introduced gene and the original gene are silenced together.

Dicer
An enzyme that cuts double-stranded RNA into short fragments such as siRNAs.

Double-Stranded RNA (dsRNA)
RNA made of two complementary strands bound together. RNA is normally single-stranded, so dsRNA is unusual and often triggers RNA interference.

Endogenous
Originating from within an organism or cell.

Gene Expression
The process by which genetic information is used to produce RNA or proteins.

Genotype
The genetic makeup of an organism—the specific DNA sequence it carries.

Guide Strand
The strand of siRNA that remains in the RISC complex and directs it to the matching target mRNA.

Knockdown
A reduction in gene expression, usually caused by RNA interference.

Messenger RNA (mRNA)
A single-stranded RNA molecule that carries genetic instructions from DNA to ribosomes for protein production.

microRNA (miRNA)
Naturally occurring small RNA molecules that regulate gene expression by blocking translation or promoting degradation of target mRNA.

Off-Target Effects
Unintended gene silencing that occurs when RNAi molecules bind to and affect genes other than the intended target.

Phenotype
The observable traits of an organism, such as appearance, behavior, or biochemical properties.

Polypeptide
A chain of amino acids linked together that forms part of a protein.

Quelling
A gene-silencing process discovered in fungi that is similar to RNA interference.

RISC (RNA-Induced Silencing Complex)
A protein complex that uses small RNAs to recognize and silence matching mRNA molecules.

Sense RNA
An RNA strand that has the same sequence as the coding strand of DNA and can be translated into protein.

siRNA (small interfering RNA)
Short double-stranded RNA molecules that guide the degradation of matching mRNA.

Transcription
The process of copying DNA into messenger RNA.

Translation
The process where ribosomes read mRNA and assemble amino acids into proteins.

Transposon
A DNA sequence that can move to different locations within the genome.

References

Chery, J. (2016). RNA therapeutics: RNAi and antisense mechanisms and clinical applications. Postdoc Journal, 4(7), 35–50. https://pmc.ncbi.nlm.nih.gov/articles/PMC4995773/

Fire, A., Xu, S., Montgomery, M. K., Kostas, S. A., Driver, S. E., & Mello, C. C. (1998).
Potent and specific genetic interference by double-stranded RNA in Caenorhabditis elegans. Nature, 391(6669), 806–811. https://doi.org/10.1038/35888

Kara, G., Calin, G. A., & Ozpolat, B. (2022).
RNAi-based therapeutics and tumor targeted delivery in cancer. Advanced Drug Delivery Reviews, 182, 114113. https://doi.org/10.1016/j.addr.2022.114113

Kim, D. H., & Rossi, J. J. (2008).
RNAi mechanisms and applications. BioTechniques, 44(5), 613–616. https://doi.org/10.2144/000112792

Howard, K. A. (2013).
RNA interference: From biology to therapeutics. Springer. https://doi.org/10.1007/978-1-4614-4744-3

Liu, J.-Y., Zhang, J., Gao, Y., et al. (2010).
Role of microRNAs in skeletal muscle development and disease. Frontiers in Bioscience (Landmark Edition), 15, 1890–1903. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3378126/

The Nobel Assembly at Karolinska Institutet. (2006, October 2).
Press release: The Nobel Prize in Physiology or Medicine 2006. NobelPrize.org. https://www.nobelprize.org/prizes/medicine/2006/press-release/

Thermo Fisher Scientific. (2026).
RNAi how-to for new users. https://www.thermofisher.com/us/en/home/references/ambion-tech-support/rnai-sirna/tech-notes/rnai-how-to–for-new-users.html

Traber, G. M., & Yu, A.-M. (2024).
The growing class of novel RNAi therapeutics. Molecular Pharmacology, 106(1), 13–20. https://doi.org/10.1124/molpharm.124.000895

Sen, G. L., & Blau, H. M. (2006).
A brief history of RNAi: The silence of the genes. FASEB Journal, 20(9), 1293–1299. https://doi.org/10.1096/fj.06-6014rev

Image citation

Alnylam Pharmaceuticals. (n.d.). How does it work? | RNAi [Video]. YouTube. https://www.youtube.com/watch?v=UPSEMBgA3C

OpenAI. (2026). How RNAi is used in therapeutics [AI-generated image]. ChatGPT (DALL·E). Generated based on RNAi mechanisms described in Kim & Rossi (2008).

OpenAI. (2026). The RNAi process [AI-generated image]. ChatGPT (DALL·E). https://chat.openai.com/

AI Use Disclosure:

We used Chat GPT to help us generate two images that accurately depicts the steps of RNAi and therapeutic applications of RNAi. We gave it source 3 by Kim, D as a reference point to ensure the information was precise. We then used other sources we had to make sure the image was accurate, legible, and a credible image for the chapter. OpenAI. (2023). ChatGPT (Mar 14 version) [Large language model]. https://chat.openai.com/chats.