Hemophilia

Cathy and Bill are a married couple who have two sons. Cathy is also pregnant with a daughter. Their youngest son, Chip, was diagnosed with hemophilia, an X-linked recessively inherited disorder. Symptoms of this disease include poor blood clotting. Cathy is unaware of any history of this disease in her family and Bill is considered healthy. Answer the following questions about this case:

1. Explain the path of inheritance that led to Chip getting this disorder. List the genotypes of Chip and both of his parents.
2. What are the chances that Cathy’s daughter will have hemophilia, and what are the chances that she will be a carrier?
3. Is this disease treatable, and what is the life expectancy for someone with this disorder?
4. Is it possible for Bill to be a carrier? Explain.
5. Is it possible for a woman to have hemophilia? If so, what is her genotype? Would X inactivation have any effect on this phenotype?