Ap biology genotypes help neededdd.?

In dogs, black (B) is dominant to chestnut (b), and solid color (S) is dominant to spotted (s). What are the genotypes of the parents that would produce a cross with 3/8 black spotted, 1/8 chestnut solid, and 1/8 chestnut spotted puppies?

(Hint: First determine what genotypes the offspring must have before you deal with the fractions.)

Ap biology genotypes help neededdd.?
Genotypes of offspring:

3/8 Black spotted B?ss

1/8 Chestnut solid bbS?

1/8 Chestnut spotted bbss

3/8 Black solid B?S?



The presence of recessive genotypes means that both parents must be at least heterozygous for recessive genes. However, if one parent had the recessive genotype (bbss) then offspring ratio should be 1/8 each. Therefore both parents are heterozygous and have BbSs phenotype.