Question

Allozyme phenotypes of alcohol dehydrogenase in the flowering plant Phox drummondii are determined by three co-dominant alleles of a single gene. In one sample of 70 plants the following data were obtained:Genotype A1A1 A2A2 A3A3 A1A2 A1A3 A2A3Number 4 24 10 10 2 20What is the frequency of the A3 allele in this sample?Multiple Choicea. 0.411b. 0.143c. 0.525d. 0.248e. 0.300

Answer 1

Answer: E. 0.300

Step-by-step explanation:

First calculate for the gene frequency = genotype/total population

I.e. for A1A1, the genetic frequency = 4/70 = 0.057. Applying the same formula will give you the genetic frequencies of;

A2A2 = 0.34, A3A3 = 0.14, A1A2 = 0.14, A1A3 = 0.03, and A2A3= 0.29.

The frequency of A3 allele = 0.14 + (1/2 × 0.03) + (1/2 × 0.29)

Frequency of A3 allele = 0.300.