Presented below is a fluorescence digital image of a Drosophila third instar wing imaginal disc labeled with apterous (a wingless mutant) in blue, vestigial (a small winged mutant) in red and Cubitus interruptus (Ci) in green. This image won 18th place in the Nikon Small World competition in 1997.

Fruit Fly Imaginal Disc: Third Instar Wing Specimen: Drosophila Imaginal Disc Technique: Fluorescence (Triple Label)

Research in the area of genetics has frequently focused on the various mutations common to the fruit fly. Defects in eye and limb formations have been particularly well documented.

One type of mutation results in the formation of wings that are abnormally small. The defect, in this instance, is caused by a mutated vestigial gene. This is an example of a recessive mutation, wherein both copies of the gene must be altered to cause the defect to be expressed.

Another type of mutation involves the development of curled wings, which is the result of a mutation of a gene on the second chromosome. This mutation is dominant, meaning only one gene of the pair need be altered to cause the defect (homozygous). In fact, if both genes carried the defect, the fruit fly would die.