Question

A cross of two Drosophila strains of genotypes z+ t+ and z t produced the following progeny: 126 z+ t+, 133 z t, 15 z+ t, and 18 z t+. What is the frequency of recombination between genes t and z?

a) 9.3%
b) 12.7%
c) 15.2%
d) 18.6%

Answer 1

The frequency of recombination between genes t and z is approximately 11.3%.

Step-by-step explanation:

The frequency of recombination between genes t and z can be calculated by determining the number of recombinant progeny and dividing it by the total number of progeny. In this case, the recombinant progeny are the individuals with the z+ t and z t+ genotypes. The total number of progeny is the sum of all four genotypes. Using the values given in the question, the frequency of recombination is:

(15 + 18) / (126 + 133 + 15 + 18) = 33 / 292 ≈ 0.113 ≈ 11.3%

Therefore, the correct answer is 11.3%, which is not one of the given options. It is important to note that recombination frequencies can range from 0% to 50% for linked genes, but in this case, the calculated frequency is less than 50%.