The Reflection on Cystic Fibrosis Frequency Calculation in the US Population

How can we calculate the frequency of the cystic fibrosis allele in the US population?

Given a frequency of 1 in 3500 individuals (f=0.0003), what is the frequency of the cystic fibrosis allele (q)?

Answer:

The frequency of the cystic fibrosis allele (q) is approximately 0.000086.

Cystic fibrosis is a genetic disorder that affects a small percentage of the population. By understanding the principles of genetics and utilizing the Hardy-Weinberg equation, we can calculate the frequency of the cystic fibrosis allele in the US population. The Hardy-Weinberg equation p² + 2pq + q² = 1 allows us to determine the frequency of different alleles in a population.

In the case of cystic fibrosis, where the frequency of the disease is 1 in 3500 individuals, we are given the value of f=0.0003. To calculate the frequency of the cystic fibrosis allele (q), we need to first identify that the frequency of individuals with cystic fibrosis (f) is equal to q².

By solving the equation q² = 0.0003, we can determine that q ≈ 0.0055. Using this information, we can then solve for p and calculate the frequency of the cystic fibrosis allele as q = 1 - p² ≈ 0.0055. Therefore, the frequency of the cystic fibrosis allele is approximately 0.000086.