Which of the following methods gave birth to idea of gene immunization ?

Options

A. Microinjection
B. Direct DNA injection
C. Biolistic
D. Both (1) & (3)

Answer

**Step-by-Step Text Solution:**

1. **Understanding Gene Immunization**: Gene immunization refers to the process of immunizing an individual by transferring a gene, which is essentially a segment of DNA. This method is also commonly known as DNA vaccination.

2. **Role of rDNA Technology**: The concept of gene immunization is closely linked to recombinant DNA (rDNA) technology. This technology involves inserting a specific gene into a DNA vector to create a DNA vaccine.

3. **Preparation of DNA Vaccine**: The DNA vaccine is prepared by incorporating the desired gene into a vector, which is then introduced into the host organism. This process allows the host to produce specific proteins that can elicit an immune response.

4. **Mechanism of Action**: Once the DNA vaccine is administered, the inserted gene gets integrated into the host's cells. The cells then express the gene, leading to the production of immunoglobulins (antibodies). These antibodies are crucial for building immunity against specific pathogens.

5. **Direct DNA Injection**: The method that primarily gave rise to the idea of gene immunization is known as direct DNA injection. This technique involves the direct introduction of the DNA vaccine into the tissues of the host, facilitating the immune response.

6. **Conclusion**: Therefore, the method that gave birth to the idea of gene immunization is direct DNA injection, which utilizes recombinant DNA technology to create DNA vaccines.

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