# How Circular Probes Find Specific DNA in Cells > This patent describes a method using special circular DNA probes and enzymes to precisely detect specific genetic sequences within a cell or tissue sample, then amplifies the detected sequences for clear viewing. - **Patent:** US 12735738 - **Original title:** Circular probes and methods for sample analysis - **Granted:** 2026 - **Status:** Active - **Times cited:** 0 - **Field:** biotech, diagnostics, research_tools, gene_editing ## What it does This method analyzes target nucleic acids, like DNA or RNA, within a cell or tissue. It uses circular probes, such as "dumbbell probes," that are designed to bind only to a specific target sequence. After the probes are introduced, an enzymatic treatment is applied. This treatment destroys any circular probes that did not bind to their target or bound incorrectly, effectively cleaning up the sample. The circular probes that successfully bound to their target nucleic acid remain intact. These intact, bound probes are then amplified using a process called rolling circle amplification (RCA), which creates many copies of the circular probe's sequence, making the target detectable. For example, a researcher could use this to find a specific viral DNA sequence inside infected cells. ## What it does NOT cover - Does not cover methods that use linear probes instead of circular probes for target nucleic acid detection. - Does not cover analysis methods that do not include an enzymatic step to remove unbound or non-specifically bound probes. - Does not cover detection systems that do not rely on rolling circle amplification (RCA) to visualize the target. - Does not cover the analysis of targets other than nucleic acids, such as proteins or lipids. - Does not cover methods where the target nucleic acid is analyzed outside of its original cellular or tissue context (i.e., not "in situ"). ## The clever bit The clever part is combining circular probes with an enzymatic step that specifically destroys only the unbound or incorrectly bound probes. This dramatically reduces background signal, ensuring that only the truly specific binding events are amplified and detected, leading to much clearer and more reliable results. ## Real-world examples 1. Detecting specific viral DNA in infected human tissue samples 2. Identifying gene expression patterns in cancer cells 3. Mapping RNA molecules within a neuron 4. Diagnosing bacterial infections by finding their unique DNA sequences 5. Studying genetic variations in individual cells ## Why it matters Precisely detecting specific nucleic acid sequences within cells or tissues is crucial for understanding diseases like cancer and infections, and for basic biological research. This method aims to improve the accuracy and clarity of such detection by reducing background noise from non-target binding. It provides a tool for scientists to visualize exactly where and how much of a particular genetic material is present in a biological sample. ## Frequently asked questions ### What does How Circular Probes Find Specific DNA in Cells cover? This patent describes a method using special circular DNA probes and enzymes to precisely detect specific genetic sequences within a cell or tissue sample, then amplifies the detected sequences for clear viewing. ### When does this patent expire? This patent is expected to expire on September 15, 2046, when the invention enters the public domain. ### What problem does this patent solve? Precisely detecting specific nucleic acid sequences within cells or tissues is crucial for understanding diseases like cancer and infections, and for basic biological research. This method aims to improve the accuracy and clarity of such detection by reducing background noise from non-target binding. It provides a tool for scientists to visualize exactly where and how much of a particular genetic material is present in a biological sample. ### What does this patent NOT cover? Does not cover methods that use linear probes instead of circular probes for target nucleic acid detection. **Full plain-English explainer:** https://patentbrief.org/patent/us/12735738/circular-probes-and-methods-for-sample-analysis **Original patent:** https://patents.google.com/patent/US12735738 --- _Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._ ## Related patents Semantically similar inventions in the PatentBrief corpus: - [How an Enzyme Helps Find Specific DNA in a Sample](https://patentbrief.org/patent/us/5210015/hcv-pcr-detection) — This patent describes a method for detecting a specific DNA sequence in a sample by using a labeled DNA probe and an enzyme that cuts the probe, releasing detectable fragments. - [How to Make Billions of Copies of a DNA Segment](https://patentbrief.org/patent/us/4683195/pcr-polymerase-chain-reaction) — This patent describes the Polymerase Chain Reaction (PCR), a method to rapidly create many copies of a specific piece of DNA or RNA, enabling its detection and analysis. - [Detecting Genetic Differences Using DNA Probes and Enzymes](https://patentbrief.org/patent/us/4683194/pcr-process) — This 1987 patent describes a method to find tiny differences in DNA sequences by using special DNA pieces (probes) and cutting enzymes, which can help diagnose genetic conditions like sickle cell anemia. - [How to Make Many Copies of a Specific DNA Segment](https://patentbrief.org/patent/us/4683202/pcr-polymerase-chain-reaction-mullis) — This patent describes the fundamental three-step process for making millions of copies of a specific piece of DNA using short starter molecules and an enzyme, a technique known as Polymerase Chain Reaction (PCR). - [How to Make Many Copies of a DNA Piece with Heat](https://patentbrief.org/patent/us/4965188/taq-polymerase-for-pcr) — This patent describes the Polymerase Chain Reaction (PCR) method, a technique to make millions of copies of a specific DNA segment using a heat-resistant enzyme and repeated temperature changes.