Real-Time PCR (Polymerase Chain Reaction) systems are molecular biological techniques used for rapid and precise amplification of nucleic acids (DNA or RNA) and detection of the presence or quantity of a specific gene. Unlike traditional PCR, Real-Time PCR allows the amplification process to be monitored in real-time, enabling instant results.

Real-Time PCR is performed within a specialized PCR device or system that utilizes fluorescent tags such as fluorophores (colored emitting compounds) or probes (specific DNA or RNA segments designed to target the nucleic acid of interest). As the amplification process progresses, the amount of the specific target nucleic acid increases, leading to an increasing emission of fluorescence from the attached tags.

Because the Real-Time PCR system can continuously determine the quantity of amplified nucleic acids, results are obtained more rapidly and with higher sensitivity. The amplification reaction involves three stages: denaturation, annealing, and extension.

Real-Time PCR finds application in a wide range of fields, including:

1. Gene expression analysis: Used to measure the expression level of a specific gene.
2. Pathogen detection: Can be employed to detect the presence of microorganisms (viruses, bacteria, fungi, etc.) causing diseases.
3. Genotype detection: Used to identify the presence or absence of specific genetic variants.
4. Cancer diagnosis: Applied in detecting specific genetic alterations associated with cancer.
5. Microorganism species identification: Can be used to determine the species or type of microorganisms in a sample.

Real-Time PCR has become an important tool in molecular biology research and clinical diagnostics. Its ability to provide rapid results, high sensitivity, and specificity makes it a preferred technique in many applications.