what is antisense technology

Options

A. When a piece of RNA that is complementary in sequence is used to stop expression of a specific gene
B. RNA polymerase producing DNA
C. A cell displaying a foreign antigen used for synthesis of antigens
D. Production of somaclonal variants in tissue cultures

Answer

### Step-by-Step Solution

1. **Understanding the Central Dogma**:
- The central dogma of molecular biology describes the flow of genetic information within a biological system. It states that DNA is transcribed into RNA, which is then translated into proteins. These proteins are responsible for the expression of traits in an organism.

2. **Role of RNA**:
- RNA is a single-stranded molecule that plays a crucial role in the process of translating genetic information into functional proteins. The sequence of nucleotides in RNA determines the sequence of amino acids in proteins.

3. **Introduction to Antisense Technology**:
- Antisense technology involves the use of a strand of nucleic acid that is complementary to a specific RNA molecule. This complementary strand can bind to the target RNA, preventing it from being translated into a protein.

4. **Mechanism of Antisense Technology**:
- When a complementary RNA strand (antisense RNA) is introduced into a cell, it binds to the target mRNA (the RNA that is supposed to be translated into a protein). This binding effectively "silences" the gene by blocking the translation process, meaning that the protein cannot be produced.

5. **Application of Antisense Technology**:
- This technology is used to inhibit the expression of specific genes, which can be beneficial in various fields such as medicine, agriculture, and biotechnology. For example, it can be used to target and silence genes that are responsible for diseases.

6. **Conclusion**:
- Therefore, antisense technology is defined as the use of a piece of RNA that is complementary in sequence to stop the expression of a specific gene. This aligns with the first option provided in the question.

### Final Answer
Antisense technology is when a piece of RNA that is complementary in sequence is used to stop the expression of a specific gene.

---