Question

In Drosophila, the yellow gene (y) and white gene (w) showed 1.3% recombination while white (w) and miniature wing gene (m) showed 37.2% recombinations. This indicates that:

• A. w and m are on different chromosomes
• B. w and m are closer than w and y
• C. w and y are on the same chromosome while m is on a different chromosome
• D. w and y are closer than w and m

Answer 1

The correct option is D w and y are closer than w and m

Yellow refers to body colour, white refers to eye colour and miniature refers to wing size in Drosophila.

Gene for body and eye color in Drosophila show 1.3% recombination while genes for eye color and wing size show 37.2% recombination.

Recombination frequency is directly proportional to distance between the genes.

The gene for body colour (y) and eye colour (w) shows less percentage of recombination when compared to genes for eye colour (w) and wing size (m). Hence, we can conclude that w and y are closer than w and m genes.