You're asking about a technique used to make multiple copies of a specific gene. That technique is called Polymerase Chain Reaction (PCR).

Here's how PCR works:

1. Denaturation: The DNA containing the target gene is heated to separate the two strands of the double helix.

2. Annealing: Primers (short sequences of DNA that are complementary to the target gene) are added and bind to the single-stranded DNA.

3. Extension: A DNA polymerase enzyme extends the primers using the single strands as templates, creating two new DNA molecules.

This process is repeated many times, each time doubling the number of copies of the target gene. PCR is incredibly powerful because it allows scientists to:

* Amplify tiny amounts of DNA: Even a single molecule of DNA can be amplified into billions of copies.

* Isolate specific genes: The primers are designed to target specific sequences, ensuring only the desired gene is amplified.

* Analyze DNA: PCR products can be used for various applications like genetic testing, disease diagnosis, and forensics.

Let me know if you'd like more detail on any specific aspect of PCR!