What are the implications of a genetic disease for a family?

Since parents can pass on their own mutations to their descendants, when faced with a genetic disease it is important to perform a family study to determine whether other members of the family carry the mutation.

Likewise, if a couple wishes to have a child, and one of the parents is affected by a genetic disease, it may be necessary to perform a genetic study to prevent the baby from inheriting the mutation that causes the disease.