There is some evidence that it can be a risk factor to have a member of your family who also has it. For example, it's more likely to have it when another member in the family also has it such as a mother or grandmother. However, it's not necessarily known yet whether it's passed down through genetics. It is developed during pregnancy and it present at birth, but it's not yet known if it is genetic. However, it is a risk factor to have a member of the family who has it.