Chapter 6, Problem 17EQ

In mice, a trait called snubnose is recessive to a wild-type nose, a trait called pintail is dominant to a normal tail, and a trait called jerker (a defect in motor skills) is recessive to a normal gait. Jerker mice with a snubnose and a pintail were crossed to normal mice, and then the mice were crossed to jerker mice that have a snubnose and a normal tail. The outcome of this cross was as follows:  

560 jerker, snubnose, pintail  

548 normal gait, normal nose, normal tail  

102 jerker, snubnose, normal tail  

104 normal gait, normal nose, pintail   

77 jerker, normal nose, normal tail   

71 normal gait, snubnose, pintail  

11 jerker, normal nose, pintail    

9 normal gait, snubnose, normal tail

Construct a genetic map that shows the order of these genes and distances between them.