Question

The Drosophila white gene is normally expressed only in cells of the eye, where it promotes red pigment production. You have identified a mutation in the white gene which causes the gene to also be expressed in the fly's wings, making them appear red (wild type flies have transparent wings). This mutation is best classified as:

A) loss of function
B) gain of function
C) haplosufficient
D) haploinsufficient
E) amorphic

Answer 1

The mutation causing red pigmentation in the wings of Drosophila due to abnormal expression of the white gene is classified as a gain of function mutation.

Step-by-step explanation:

The mutation in the Drosophila white gene that leads to its expression in the wings, causing red pigment production where it normally would not occur, is best classified as a gain of function mutation. This type of mutation leads to a gene acquiring new functions or expressing in additional tissues. As a result, mutant flies with this gain of function in the white gene will show the novel phenotype of red wings, in contrast to transparent wings observed in the wild type.