The gene for cystic fibrosis is located over chromosome

Options

A. 21 chromosome
B. 14 chromosome
C. 7 chromosome
D. 4 chromosome

Answer

To determine the chromosome on which the gene for cystic fibrosis is located, follow these steps:

### Step-by-Step Solution:

1. **Understand Cystic Fibrosis**: Cystic fibrosis is a genetic disorder that affects the respiratory and digestive systems. It is important to identify the gene responsible for this condition.

2. **Identify the Gene**: The gene responsible for cystic fibrosis is known as the CFTR gene, which stands for Cystic Fibrosis Transmembrane Conductance Regulator.

3. **Locate the Chromosome**: Research indicates that the CFTR gene is located on chromosome 7. Specifically, it is found on the long arm (Q arm) of this chromosome.

4. **Review the Options**: The options provided are:
- 21st chromosome
- 14th chromosome
- 7th chromosome
- 4th chromosome

5. **Select the Correct Option**: Since the CFTR gene is located on chromosome 7, the correct answer is the 7th chromosome.

### Final Answer:
The gene for cystic fibrosis is located on the **7th chromosome**.

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