Hemophilia is an X-linked condition caused by a recessive gene.
Example: Hemophilia A. Hemophilia A is an X-linked recessive disease caused by a lack of a coagulant, or blood clotting agent, called factor VIII (factor 8). This is caused by a mutation in a gene on the X chromosome called F8.If a father is affected, his daughters will be carriers of hemophilia A and his sons will be unaffected.or an X-linked dominant condition, only one copy of a gene on the X chromosome whether in a female with two X chromosomes or males with on X chromosome must have a change or mutation for an individual to be affected with the condition.