Question

In the fruit fly, Drosophila melanogaster, a known deletion on the X chromosome removes both a gene involved in the fly's development and the gene for eye color. The deletion is lethal when homozygous or hemizygous. Flies that are heterozygous for the mutation are viable, but have indentations at the wing margin. Therefore, the deletion is named the Notch mutation. The allele for wild type eyes is dominant over the allele for white eyes.

Predict the phenotypic ratio of the offspring from a cross between a white-eyed notched female and a wild type male.
a. 1 white-eyed notched female 1 wild type female 1 notched male 1 white-eyed male
b. 1 wild type female 1 notched female 1 white-eyed male
c. 1 white-eyed female 1 notched female 1 white-eyed male
d. 1 wild type female 1 notched female 1 white-eyed male 1 white-eyed notched male

Answer 1

1/3 Wild Type Males, 1/3 Wild Type Females, 1/3 White Eyed Notch Females