The frequency of an allele in an isolated population may change due to

Options

A. Genetic drift
B. Gene flow
C. Mutation
D. Natural selection.

Answer

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

1. **Understanding the Question**: The question asks about the factors that can lead to a change in the frequency of an allele in an isolated population.

2. **Identifying the Options**: The options provided are:
- Genetic drift
- Gene flow
- Mutation
- Natural selection

3. **Analyzing Genetic Drift**:
- Genetic drift refers to random changes in allele frequencies that occur in small populations.
- In an isolated population, where there is limited genetic exchange with other populations, genetic drift can significantly affect allele frequencies due to random sampling effects.

4. **Considering Gene Flow**:
- Gene flow involves the transfer of alleles or genes from one population to another.
- In an isolated population, gene flow is minimal or absent, which means it does not contribute to changes in allele frequency.

5. **Evaluating Mutation**:
- Mutation is a change in the DNA sequence that can introduce new alleles into a population.
- While mutations can affect allele frequency, they are not the primary mechanism for change in a small, isolated population.

6. **Examining Natural Selection**:
- Natural selection is the process where organisms better adapted to their environment tend to survive and produce more offspring.
- Although natural selection can influence allele frequencies, it typically requires a variation in fitness among individuals, which is not the primary focus in an isolated population context.

7. **Conclusion**:
- Given that the question specifies an isolated population, the most relevant mechanism for changes in allele frequency is genetic drift.
- Therefore, the correct answer is **genetic drift**.