Question

You are studying a population of rattlesnakes and you find the following allele frequencies: f(A1A1) = 0.72 f(A1A2) = 0.26 f(A2A2) = 0.02. What is the frequency of the A1 allele in your population?

1) 0.15
2) 0.25
3) 0.28
4) 0.52
5) 0.85

Answer 1

To calculate the frequency of the A1 allele, we sum the contributions of A1 from the homozygous (A1A1) and heterozygous (A1A2) genotypes. After performing the calculation, the frequency of the A1 allele in the rattlesnake population is determined to be 0.85. The correct answer is option 5.

Step-by-step explanation:

The student is asking about allele frequency within a population of rattlesnakes. The provided allele frequencies are for two genotypes: homozygous (A1A1 and A2A2) and heterozygous (A1A2). To find the frequency of the A1 allele, we need to sum the frequency of A1 in all the genotypes where it appears.

The frequency of the A1 allele is given by 2 * f(A1A1) + 1 * f(A1A2), since homozygous individuals (A1A1) have two copies of the A1 allele and heterozygous individuals (A1A2) have one. Therefore:

• Frequency of A1 allele from A1A1 individuals = 2 * f(A1A1) = 2 * 0.72 = 1.44
• Frequency of A1 allele from A1A2 individuals = 1 * f(A1A2) = 1 * 0.26 = 0.26
• Total frequency of A1 allele in the population = 1.44 + 0.26 = 1.70

Since each individual has two alleles for this gene, the total number of alleles in the population is twice the number of individuals. To get the actual frequency, we divide the total frequency of the A1 allele by 2, resulting in 0.85. Therefore, option 5) 0.85 is the correct frequency of the A1 allele in the population.