THE MOLECULAR BASIS OF INHERITANCE
THE GENETICS OF VIRUSES AND BACTERIA
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Detailed explanation-1: -A man with hemophilia (a recessive, sex-linked blood clotting disorder) has a daughter of normal phenotype. She marries a man who is normal for the trait. Since this is a recessive disorder, one XH allele will give a normal phenotype.
Detailed explanation-2: -So a carrier’s son has a 50% chance of having hemophilia. A baby girl will inherit an X chromosome with a dominant gene for normal blood clotting from her father. So the daughter will not have hemophilia.
Detailed explanation-3: -Hemophilia A and hemophilia B are inherited in an X-linked recessive pattern . The genes associated with these conditions are located on the X chromosome, which is one of the two sex chromosomes . In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition.