A woman with two genes for haemophilia and one gene for colour blindness on one of the 'X' chromosomes marries a normal man. How will the progeny be?
Correct answer: B. 50% haemophilic daughters (carrier) and 50% colour blind daughters (carrier)
- A. 50% haemophilic colourblind sons and 50% normal sons
- B. 50% haemophilic daughters (carrier) and 50% colour blind daughters (carrier)
- C. All sons and daughters haemophilic and colourblind
- D. Haemophilic and colourblind daughters
Explanation
When a woman with two genes for hemophilia and one gene for color blindness on one of her X chromosomes marries a normal man, their progeny can include daughters who are carriers of both traits (hemophilia and color blindness) and normal daughters. Sons are not possible in this scenario because the woman can only pass on X chromosomes.
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About Inheritance
Mendel's laws explain segregation, independent assortment and the prediction of genetic ratios using alleles, genotypes and phenotypes. The chapter also covers linked genes, recombination and crossing over during meiosis, then applies pedigree reasoning to X-linked recessive traits, which show different inheritance patterns in males and females.
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