How is hemophilia spread?

Inheritance/genetics: Hemophilia is a disorder of clotting due to abnormal genes that are inherited from the mother by the son. Daughters are carriers but generally do not suffer from it. An affected man pass the gene to his daughters but can not pass it to the sone. Daughters pass the disease on to their sons. Rarely a new mutation, de novo, may occur to cause the disease that is then spread to the offspring.