Question

What are the chances of offspring being a homozygous with a disorder if the parents are heterozygous carriers?A) 1B) 75%C) 50%D) 25%

Answer 1

To answer the question first we have to do the Punett square for this case. As it says in the question both parents are heterozygous meaning that they have two different alleles for the gene that causes the disorder.

So we do the Punett square as follows:

As we can see from the Punett square the chances of the offspring being homozygous (having two identical alleles of a particular gene) are 1 out of 4, in other words 25%.

So the answer is D) 25%