The probability of having a haemophilia carrier daughter by a haemophilia carrier mother and a normal father is: |
100% 50% 25% 75% |
25% |
The correct answer is Option (3) → 25% Hemophilia is an X-linked recessive disorder. A carrier mother has one normal X chromosome and one hemophilia-carrying X chromosome (XhY). A normal father has one normal X chromosome and one normal Y chromosome (XY). Cross Analysis: When we cross the genotypes, we get four possible combinations for their children:
Probability Calculation: Out of these four possibilities: There is one carrier daughter genotype XhX out of the total four possible outcomes. So:
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