Hi you posted this on your own page. If you wish responses please start a thread on the forum. Since this is about your concerns for your own health use the do I have ALS subforum. However if only one relative has had ALS your risk is about the same as anyone else NOT 50 percent. Read the sticky in the FALS section to learn more. 50 percent applies if a parent or sibling had ALS plus other close relatives had ALS as well