Neurofibromatosis 1 and multiple sclerosis.

Neurofibromatosis 1 is a common autosomal dominant disease that principally involves the skin and peripheral nervous system. The gene for the disorder has been located on chromosome 17q11.2 and there are three embedded genes within the neurofibrosis gene. One of these genes codes for oligodendrocyte-myelin glycoprotein, is found in the CNS during myelination, and may have a role in myelin formation. The case histories of five patients, including two siblings, who have both neurofibromatosis 1 and multiple sclerosis are reported. All five had the primary progressive form of multiple sclerosis, which forms only 15% of multiple sclerosis in population surveys. The coincidence of neurofibromatosis 1 and multiple sclerosis might be due to a mutation in the embedded oligodendrocyte-myelin glycoprotein gene.