My mother has AMN. Similarly, my grandfather and two great great uncles were afflicted with a neurological condition.
She was actually first diagnosed with MS and, fearing for me and the likelihood that it was passed on genetically she prompted me to go to a geneticist.
My GP made an appointment for me; I went gave my history and, sensing something, the geneticist had my Mum come in give more history and a blood sample for testing. The sample was sent to Johns Hopkins and there they discovered a defect in the ABCD1 gene. (My own result, later, was negative - phew!)
To the best of my knowledge, then, if you're able to have the ABCD1 gene tested, you should be able to find out conclusively if you're a carrier or not.
I can't say what your "chances" are but AMN usually only manifests itself men, and women are usually only carriers, I was informed. My Mum wasn't so lucky, it seems.
I hope you have an easy time getting yourself tested, and pray that you receive a negative result!