Chimeric DNA used for:
**Core Concept**
Chimeric DNA refers to a type of recombinant DNA molecule that is created by combining DNA sequences from two or more different sources. This technique is commonly used in molecular biology to study gene function, expression, and regulation.
**Why the Correct Answer is Right**
The correct answer is used in the creation of chimeric antigen receptors (CARs) for immunotherapy. CARs are designed to redirect T cells to recognize and destroy cancer cells by combining the antigen-binding domain of an antibody with the T-cell receptor (TCR) signaling domain. This allows T cells to recognize and target specific antigens on cancer cells, leading to cell death. The chimeric DNA is used to engineer T cells to express the CAR, which is then used to treat various types of cancer.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because chimeric DNA is not primarily used for gene editing, although it can be used in conjunction with gene editing tools like CRISPR/Cas9.
**Option B:** This option is incorrect because chimeric DNA is not used for vaccine development, although it can be used to express vaccine antigens.
**Option C:** This option is incorrect because chimeric DNA is not used for gene therapy, although it can be used to express therapeutic genes.
**Clinical Pearl / High-Yield Fact**
Chimeric antigen receptors (CARs) have shown significant promise in the treatment of various types of cancer, including leukemia, lymphoma, and solid tumors. CAR-T cell therapy is a type of immunotherapy that involves engineering a patient's T cells to recognize and destroy cancer cells.
**Correct Answer: C. Gene therapy.