Question

A woman with type O blood is expecting a child. Her husband is type A. Both the woman's father and her husband's father had type B blood. What is the probability that the child will have type O blood?A.100%b.75%C.50%D.25%E.0%

Answer 1

C. 50%

Explanation:

• The woman has blood group O so her genotype will be $i^{O} i^{O}$.
• The husband has blood group A so his genotype could either be $I^{A} I^{A} or I^{A} I^{O}$.
• Since the husband's father was having blood group B so it is obvious that the husband is heterozygous with genotype $I^{A}i^{O}$.
• A cross between heterozygous dominant and homozygous recessive is a test cross and will yeild 50% offspring with recessive genotype.
• So the probability of the child having blood group O is 50%.