How Hemophilia is Inherited

The following examples show how the hemophilia gene can be inherited. It is important to note that in one-third of people with hemophilia, there is no family history of the disorder.

1. In this example, the mother is a carrier of the hemophilia gene, and the father does not have hemophilia.
   • There is a 50% chance that each son will have hemophilia.
   • There is a 50% chance that each daughter will be a carrier of the hemophilia gene.

2. In this example, the father has hemophilia, and the mother does not carry the hemophilia gene.
   • All daughters will carry the hemophilia gene.
   • No sons will have hemophilia.

3. In this example, the father does not have hemophilia, and the mother does not carry the hemophilia gene.
   • None of the children (daughters or sons) will have hemophilia or carry the gene.

References