Problem2

You cross a true-breedingyellow-bodied, smooth-winged female fly with a true-breedingred-bodied, crinkle-winged male. The red body phenotype is dominantto the yellow body phenotype and smooth wings are dominant tocrinkled wings. Use B orb for body color alleles, andW or w for wingsurface alleles.

a) What are the genotypes of the Pgeneration flies?

b) What will be the genotype(s) andphenotype(s) of the F1 offspring?

c) You discover thatthe genes for body color and wing surface are linked. You perform adihybrid test crossbetween the F1 flies from part (b) with atrue-breeding yellow-bodied, crinkle-winged fly. Use thefollowingF2 results to determine the recombination frequency (%)between the body color and wing surface genes. (Remember that therecombinants are the ones that do not resemble the parental typesfrom the P generation.)

Body Color	Wing Surface	# of Individuals
red	smooth	102
yellow	smooth	404
red	crinkled	396
yellow	crinkled	98

You decide to turn your attention toa different gene, one that controls wing length. This gene has twoalleles, \"L orl\" where long wings are dominant to short wings.Remember that the red body phenotype is dominant to the yellow bodyphenotype. You again mate two true-breeding flies:

P: red-bodied,short wing male X yellow-bodied, long wing female

F1: All red-bodied,long wing

d) You perform atest cross between the F1 flies above with true-breedingyellow-bodied, short-winged flies. You get the following F2results. What is the recombination frequency (%) between the genesfor body color and winglength?

Body Color	Wing Length	# of Individuals
red	long	45
red	short	460
yellow	long	440
yellow	short	55

e) Based on theinformation in (c) and (d), what are the two possible arrangementsof these three genes: bodycolor, wing surface and wing length? Drawtwo linkage maps to show the possible arrangements of thesegenesand the map distance between genes.