A genetics student identified a male fly (Drosophila) that had an XX genotype. Which of the following is the MOST accurate plausible explanation?

Question

Quizplus · Accepted Answer

The fly could have a mutation in either its sex-lethal (Sxl) or transformer (tra) gene.Sxl is the master regulator of sex determination in Drosophila. In males, Sxl is not expressed, and tra is not spliced. This results in the production of male-specific proteins, such as doublesex (dsx), which promote the development of male secondary sexual characteristics. In females, Sxl is expressed, and tra is spliced. This results in the production of female-specific proteins, such as female-specific doublesex (fsdsx), which promote the development of female secondary sexual characteristics.A mutation in either Sxl or tra could result in the development of a male fly with an XX genotype. For example, a mutation in Sxl could prevent the expression of Sxl, which would lead to the production of male-specific proteins and the development of male secondary sexual characteristics. Similarly, a mutation in tra could prevent the splicing of tra, which would also lead to the production of male-specific proteins and the development of male secondary sexual characteristics.

A Genetics Student Identified a Male Fly (Drosophila) That Had