For linked genes A, B, and C, the fraction of single crossovers for genes A and B is 0.1, the fraction of single crossovers for genes B and C is 0.3, and the fraction of double crossovers is 0.03. Which of the following statements is true? For linked genes A, B, and C, the fraction of single crossovers for genes A and B is 0.1, the fraction of single crossovers for genes B and C is 0.3, and the fraction of double crossovers is 0.03.

Which of the following statements is true?

A. The distance between A and B is less than the distance between B and C.

B. Interference has affected the number of double crossovers.

C. The distances between A and B and B and C are approximately equal.

D. The distance between A and B is greater than the distance between B and C.

The distance between A and B is less than the distance between B and C.

Explanation:

Crossing over is the exchange of genetic segments that occurs between the chromatids of homologous chromosomes during prophase I of meiosis I. The process of crossing over requires the genes to be present on different chromosomes.

Linked genes are the ones that are present on the same chromosome. Linked genes that are present far apart on the same chromosome may undergo crossing over but the genes present close to each other on the same chromosome are least likely to undergo crossing over. Therefore, the frequency of crossing over increases with increased distance between the genes.

According to the given information, crossing over frequency between genes A and B is 0.1 while that for the genes B and C is 0.3. Since the genes B and C have more crossing over frequency, they are located far apart from each other than the genes A and B. Distance between A and B genes is less than the distance between B and C genes.