Fur colour in jackalopes can be cream yellow brown or black

Fur colour in jackalopes can be cream, yellow, brown or black. In separate crosses of true-breeding parents, we obtained the following data.

Cross       P1 parents       F1 offspring   F2 offspring                  

A       Black x brown       All black 3/4 black; 1/4 brown

B       Yellow x brown All black 9/16 black; 3/16 brown; 3/16 yellow; 1/16 cream

C       Black x yellow All black 3/4 black; 1/4 yellow

a) Based upon the data, how many genes control coat colour? Briefly explain your answer.

b) Create genetic symbols for these gene(s) and their alleles, and indicate the genotypes of the parents in the P1 generation for each of the crosses (A-C) above.

Solution

Answer:

1).Two genes with four alleles (each two alleles) control the color of the fur

A_B_ = Black

A_bb = Brown

aaB_ = Yellow

aabb = Cream

2)

A ) Black x brown = F1- All black 3/4 black; 1/4 brown

AABB x AAbb AABb & AaBb