Albinism is a recessive trait. A man and woman both show normal pigmentation, but both have one parent who has albinism (without melanin pigmentation). What is the probability that their first child will have albinism?
A) 0
B) 1/2
C) 1/4
D) 1

Question

Quizplus · Accepted Answer

The parents are both carriers of the recessive allele for albinism. This means that they each have a 50% chance of passing on the recessive allele to their child. 
If both parents pass on the recessive allele, then their first child will have albinism. 
Therefore, the probability of their first child having albinism is 1/2 x 1/2 = 1/4 or 25%, which corresponds to choice C.

Albinism Is a Recessive Trait