Abby, If your Mom and Aunt have not been tested for a B12 deficiency, get them tested pronto! And don't take a low reading - even in the normal range - as normal. A B12 deficiency begins even at higher levels. Pernicious anemia is also a thought. Homocysteine (mine was high during my def.) and methylmalonic acid can be elevated during a B12 deficiency and that alone can cause neurological symptoms.

Mike, There are actually many blood tests for the genetic mutations of a CMS. Since Mayo was the leader in this area to begin with, they have the means to test for it more easily. Not many labs have the money to afford such specialized testing. Your neuro would have to call to see if they would just run some blood tests or if they would want to see you - AND your sister at the same time.

Annie