Short Horns vs Long Horns: A Genetic Mystery Unraveled

What are the most likely genotypes of the parents?

A. SS and ss

B. Ss and ss

C. SS and Ss

D. Ss and Ss

Why is (C) not the right answer?

Correct answer - D Ss and Ss.

Answer:

The most likely genotypes of the parents are D. Ss and Ss.

In the case of short horns (S) being dominant over long horns (s), the punnet square reveals the following possibilities: SS, Ss, Ss (3 Short horns), and ss (1 Long horns).

When two short horn cows are bred and produce four offspring, with three having short horns and one having long horns, the most likely genotypes of the parents are both Ss. This is because both parents must carry the recessive allele (s) in order to produce offspring with long horns.

Therefore, the correct answer is D. Ss and Ss.