Question

If a person with o blood type produces offspring with a person with b blood type, then what percentage of their offspring will be type o in the best case scenario?

Answer 1

In humans, blood group is determined by three alleles
`I^(A)`,
`I^(B)`, and
`i`.

`I^(A)` and
`I^(B)` are co-dominant whereas
`i` is recessive to other two.

Thus, if a person with blood group O produces offspring with blood group B then the other parent must contain
`I^(B)` allele.

The genotype of other person can be
`I^(A)I^(B)`,
`I^(B)I^(B)`, or
`I^(B)i`.

There is only one condition in which the person can have offspring with blood group O that is, when the other parent is
`I^(B)i`.

In this condition, the probability of an offspring to have blood group O is 50%.

In other conditions, the probability of an offspring to have blood O is 0%.