Hi and welcome. so sorry your mom has been dx'd with ALS. That is tough not only on her but all of the family. May I ask when she was diagnosed?
My brain is mush tonight and I would like to answer some of the o-band questions but I want to get it right, so I'm not going to attempt it right now.
I did a quick google and here's a good page from a book on this question - sorry the link is so long to copy but it points out that o-bands are found in ALS.
http://books.google.com/books?id=Mbb5WZxY75wC&pg=PA128&lpg=PA128&dq=als+and+oligoclonal&source=bl&ots=owZLRCBS-t&sig=9ARDxbEg89WKeEkO7-Ic-H0XUQk&hl=en&ei=1HVkTb-qGcT38Aar_b3EBg&sa=X&oi=book_result&ct=result&resnum=1&sqi=2&ved=0CBcQ6AEwAA#v=onepage&q=als%20and%20oligoclonal&f=false
From an earlier MH post -
http://www.medhelp.org/posts/Neurology/IgG-Index-and-Oligoclonal-bands-Indicating-MS-Only/show/293836
"The oligoclonal band detection means that you have selected production of antibodies in your CSF/brain. It does not mean that you have MS, only that your brain (the immune cells that have migrated to your brain) are producing antibodies. This can happen in many disease states, from infection to autoimmune diseases."
good luck with sorting this out with your mom - and be sure to talk to the doctors about this question.
best, Lulu