1. A gene called “Forked” (f) produces shortened, bent, or split bristles and hairs in Drosophila. A second gene called “outstretched” (od) results in wings being carried at right angles to the body. A third gene called “garnet” (g) produces pinkish eye color in young flies. Wild-type females heterozygous at all three gene loci were crossed to males that are wild type at all loci. The F1 data is shown below:
F1: Females : all wild type
Males 57 garnet, outstretched
419 garnet, forked
60 forked
1 outstretched, forked
2 garnet
439 outstretched
13 wild type
9 outstretched, garnet, forked
_____
1000
A. Which gene is in the middle?
B. On what specific chromosomes type are these genes likely to reside (autosomes or sex chromosomes)?
C. What is the linkage relationship between alleles at the forked and outstretched loci in the maternal parent? Specific terminology must be used to describe this relationship.
D. Calculate the map distances (draw map).
E. Calculate the interference.
Help please!!!
Ok, so I know that the gene in the middle is g. the two recombinant genotypes are g+ od f and g od+ f+. The two non recombinant genotypes are g+ od f+ and g od+ f. This is where I get stuck. I dont know the answer for part b or c. all I know is that flies can only undergo crossing over if they're females. I think part c is the linkage relationship between the alleles in the female corresponds to the transfiguration or repulsion configuration.
Please help me with point B. and C if my answer is incorrect.
Thank you!!
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