Whereas heterozygous women with AMN never develop the cerebral form (unless they have ABCD1 gene mutation on both alleles), 35 % of AMN males develop a cerebral demyelinating form of the disease between 20 and 35 years of age with the same outcome as in young boys toward vegetative state or death few years after the onset of neurologic symptoms. This evidence concerns the gene ABCD1 and adrenomyeloneuropathy.