What is the probability of having children with 'O' blood group, where both mother and father are heterozygous for 'A' and 'B' blood group, respectively ?
- 0%
- 50%
- 25%
- 75%
Answer
(3) 25%
Solution
Mother heterozygous for blood group A ⇒ genotype IAi
Father heterozygous for blood group B ⇒ genotype IBi
Cross: IAi IBi
⇒ Offspring: IAIB (AB), IAi (A), IBi (B), ii (O), each with probability 14
∴ Probability of a child with blood group O = 14 = 25\%
Answer: (3)