In the film, Peter Parker asks whether the device uses target-specific short interfering RNA, usually shortened to siRNA. These small RNA molecules can be designed to recognize a particular messenger RNA, or mRNA.
Messenger RNA carries instructions copied from DNA to the cell's protein-making machinery. An siRNA guide can direct a cellular complex known as RISC to matching mRNA. The complex then cuts the target, reducing production of the corresponding protein.
This process is often called gene silencing, but the name can be misleading. The treatment does not remove or switch off the underlying DNA. It lowers the output of a selected gene, and the effect can wear off.
RNA interference is established medicine, not science fiction. Several siRNA drugs have been approved by the US Food and Drug Administration for conditions including hereditary amyloidosis, acute hepatic porphyria, primary hyperoxaluria, high cholesterol, hemophilia and familial chylomicronemia syndrome.
The fictional application presents much bigger problems. Spider-Man's abilities would presumably involve many proteins, tissues and biological pathways. A single siRNA target would be unlikely to suppress strength, reflexes, senses and other traits together. Targeting several genes would also increase the challenge of predicting side effects.
Delivery is another major obstacle. Most approved siRNA medicines are designed to reach the liver, although one approved product uses lipid nanoparticles and researchers are testing ways to reach other organs. A whole-body treatment affecting muscles, nerves and other tissues would be far more difficult.
Real siRNA drugs also do not behave like an instant switch. They generally reduce rather than eliminate production of a protein. Their effects vary by drug and can last for weeks or months. Even after the silencing effect declines, cells may need time to rebuild the affected proteins.
The film therefore uses a genuine biological mechanism as a plausible idea, not a technology that medicine can currently reproduce. RNA interference can selectively reduce protein production, but it cannot safely fine-tune fictional superpowers on demand.
Source: sciencenews.org