Three X-linked genes with recessive mutant phenotypes are found in Drosophila: garnet eyes (g), crossveinless wings (cv),
Question:
Three X-linked genes with recessive mutant phenotypes are found in Drosophila: garnet eyes (g), crossveinless wings (cv), and forked bristles (f). A female with garnet eyes, forked bristles and normal wings is crossed with a male that exhibited crossveinless wings. F1 females were wild-type for all three traits, and F1 males had garnet eyes and forked bristles. When F1 flies were mated with each other, the following results were obtained (note that only male F2 flies were counted).
Phenotypes Number
Wild-type 0
Garnet, Forked, Crossveinless 2
Garnet 69
Forked, Crossveinless 82
Garnet, Crossveinless 555
Forked 598
Crossveinless 136
Garnet, Forked 157
A. Diagram the genotype of the P and F1 plants used in these crosses.
B. Draw a chromosome map with the correct distances (rounded to one decimal point) noted between adjacent
C. Which two genes are most closely linked?
Biochemistry Concepts and Connections
ISBN: 978-0321839923
1st edition
Authors: Dean R. Appling, Spencer J. Anthony-Cahill, Christopher K. Mathews