The formula of genetic drift that occurs in small isolated population is

Options

A. `GD prop (sqrt(pn))/(q)`
B. `GD prop (sqrt(pq))/(n)`
C. `GD prop (sqrt(n))/(pq)`
D. `GD prop (sqrt(pn))/(p)`

Explanation

To solve the question regarding the formula of genetic drift that occurs in small isolated populations, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Genetic Drift**:
- Genetic drift refers to the random fluctuations in the frequency of alleles (gene variants) in a population. This is particularly pronounced in small, isolated populations where chance events can significantly impact allele frequencies.

2. **Identify the Formula for Genetic Drift**:
- The formula for genetic drift in a small population is expressed as:
\[ GD \propto \sqrt[3]{\frac{pq}{n}} \]
- Here, \( GD \) represents genetic drift, \( p \) and \( q \) are the frequencies of two different alleles, and \( n \) is the total number of alleles in the population.

3. **Explain the Components of the Formula**:
- **\( p \)**: Frequency of the first allele.
- **\( q \)**: Frequency of the second allele.
- **\( n \)**: Total number of alleles in the population.
- The formula indicates that genetic drift is directly proportional to the cube root of the product of the allele frequencies divided by the total number of alleles.

4. **Determine the Relationship**:
- From the formula, we can see that genetic drift increases when the product \( pq \) increases or when the population size \( n \) decreases. This means that in smaller populations, genetic drift can have a more pronounced effect.

5. **Evaluate the Options**:
- Given the options, we can identify that the correct statement regarding genetic drift is:
- **Option B**: \( GD \) is directly proportional to the cube root of \( \frac{pq}{n} \).

### Final Answer:
The formula of genetic drift that occurs in small isolated populations is:
\[ GD \propto \sqrt[3]{\frac{pq}{n}} \]
The correct option is **Option B**.

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