NEETZoologyPrinciples of Inheritance and Variation
A man with blood group AB and normal colour vision marries a woman with blood group O who is a carrier for colour blindness. What is the probability that their first child will be a son who has blood group A and is colour-blind?
Options
- A1 4
- B1 16
- C1 8
- D1 2
Correct answer
C. 1 8
Step-by-step solution
The inheritance of ABO blood groups and colour blindness (a sex-linked recessive trait) assort independently. For blood groups: The father has blood group AB (genotype I^A I^B ) and the mother has blood group O (genotype ii ). A cross between them ( I^A I^B ii ) yields progeny with either blood group A ( I^A i ) or blood group B ( I^B i ) in equal proportions. Probability of the child having blood group A = 1 2 . For colour blindness and sex: The father has normal vision (genotype X^C Y ) and the mother is a carrie