What differentiates familial hemiplegic migraine from standard hemiplegic migraine?
Familial hemiplegic migraine is due to a genetic mutation that can be traced to two or more members of the same family, whereas someone with sporadic hemiplegic migraine has no other family member with the disease.
“Familial hemiplegic migraine is due to a mutation in one of at least three genes we know about now. That accounts for about 70% of patients. That means that we haven't discovered all of the genes that account for hemiplegic migraine. Familial hemiplegic migraine, you've got someone in the family, or you've got multiple members of the family who have hemiplegic migraine. So it's familial, and it's due to a mutation either that we can find by doing genetic testing, or we can't find even if we do genetic testing, because we haven't discovered the gene yet.
“Sporadic hemiplegic migraine is hemiplegic migraine in an individual with no family history. Nobody in the family has it ... Sometimes it's due to a mutation in one of these genes. You can develop a de novo mutation. You're the first one to actually get the mutation in that gene, even though nobody's had it in your family or maybe there are other genes that we just haven't discovered yet, where patients will develop a spontaneous, or de novo, mutation;, they're the first in the family and we just haven't discovered those genes yet. So there is sporadic hemiplegic migraine, familial hemiplegic migraine — the thing is they look the same, they sound the same, and they're treated the same.”
Familial hemiplegic migraine is due to a genetic mutation that can be traced to two or more members of the same family. It can also occur in multiple members of the same family due to a mutation in a gene that has yet to be discovered. On the other hand, someone with sporadic hemiplegic migraine has no other family members with the disease. This occurs because the individual is the first one in the family to spontaneously develop a gene mutation, or de novo mutation. Both forms of hemiplegia, however, are treated in the same manner.
David Dodick, MD
Mayo Clinic, Arizona
David Dodick, M.D., FAAN, is a professor of neurology at the Mayo Clinic College of Medicine and Science in Scottsdale, Arizona. He is the director of the headache program and the sports neurology and concussion program at Mayo Clinic in Arizona. He is an adjunct professor in the department of neurosciences, Norwegian University of Science and Technology. Dr. Dodick is board certified by the Royal College of Physicians and Surgeons of Canada and the American Board of Psychiatry and Neurology (ABPN). He also holds United Council for Neurologic Subspecialties certification in headache medicine and ABPN certification in vascular neurology.
Dr. Dodick has authored more than 380 peer-reviewed publications and authored/edited 10 books. He is the chair of the American Migraine Foundation, chair of the American Academy of Neurology (AAN) Annual Program Concussion Committee, co-director of the American Registry of Migraine Research, chair of the International Registry for Migraine Research, chair of the International Headache Society Global Patient Advocacy Coalition, co-director of the Annual AAN Sports Concussion Conference, president-elect of the International Concussion Society, immediate past-president of the International Headache Society, former editor-in-chief of Cephalalgia, and past-president of the American Headache Society.