People who are known to be lactose intolerant do the lactose digesting enzyme, lactase . This happens because the lactase producing gene is shut off in their cells connected to the digestive system . Which of the following process is not occurring for the mentioned gene ?

Options

A. Translation
B. Mutation
C. Replication
D. Transcription

Answer

To solve the question regarding lactose intolerance and the processes involved with the lactase-producing gene, we need to analyze the options provided and understand the biological processes that occur in gene expression.

### Step-by-Step Solution:

1. **Understanding Lactose Intolerance**:
- Individuals who are lactose intolerant do not produce the enzyme lactase, which is necessary for digesting lactose. This is due to the lactase-producing gene being "shut off" in their cells.

2. **Identifying the Processes**:
- The question asks which process is **not occurring** for the lactase-producing gene. The processes listed are:
- A) Translation
- B) Mutation
- C) Replication
- D) Transcription

3. **Analyzing Each Process**:
- **Replication**: This is the process where DNA is copied. Since the gene is present, replication can occur.
- **Transcription**: This is the process where DNA is transcribed into mRNA. Since the gene is "shut off," transcription is not occurring.
- **Translation**: This is the process where mRNA is translated into a protein (in this case, lactase). If transcription does not occur, translation cannot happen.
- **Mutation**: This refers to a change in the DNA sequence. The question does not indicate any change in the DNA sequence, so mutation is not relevant here.

4. **Conclusion**:
- Since the lactase-producing gene is shut off, the process that is not occurring is **Transcription**. Without transcription, the gene cannot be expressed, and therefore, the enzyme lactase cannot be produced.

### Final Answer:
**D) Transcription**