What causes thalassemia?
It is passed from parent to child. A defect in one or more genes causes it. Both parents must carry a gene for the disease in order to pass it to their child. If you, either parent, or any of your siblings have thalassemia or carry a gene for it and you’re thinking about having a child, you may want to talk to a genetic counselor before you get pregnant. A genetic counselor can tell you how likely it is that your child will have the disease and how severe it might be.
