Question

Pedigree Applications 1. The gene for spotted coat color in rabbits (R) is dominant to its allele for solid color (r). In the pedigree given below, assume that those individuals brought in the family do not carry the gene for solid color, unless there is evidence to the contrary. Further, assume that the probabilities that individuals IVI and IV2 will be careers for this trait are 7/12 and 11/24, respectively. Solid symbols represent solid colored bunnies, and open symbols represent spotted bunnies. Calculate the probability of solid colored bunnies being produced from the following matings: (15 points) 4 9 10 a. IIII x IV3 b. IVI x IV2 c. IVI x IV3 e. 112 x 1119

If you can explain clearly in steps I would greatly appreciate it.

Thank you.

Answer 1

square is male and circle is female

since spotted colour is dominant which means if spotted colour is present with solid colour then only spotted colour will be seen in generation

this is an example of autosomal recessive pedegree as parents are unaffected while child is affected. one more important thing is second generation is affected but nobody is affected in third generation while fourth generation act as carrier, they have trait but not expressing.

a. III1 $\times$ IV3

there is no chance that individuals are affected so probability is zero

b.IV1 $\times$ IV2

7/12*11/24

c. IV1 $\times$ IV3

7/11*0

so it will be zero

d.III2 $\times$ III9 will also be zero

e. II2 $\times$ III9 will also be zero