In a new study, published in the American Journal of Human Genetics, researchers were able for the first time to convincingly demonstrate a genomic locus to be linked to migraine susceptibility in two diverse populations.
Migraine is the most common cause of episodic headache, and by far the most common neurological cause of a doctor’s visit. It affects some 15% of the population, including some 41 million people in Europe, and places a considerable burden on healthcare in both the developed and the developing world.
During the last few years, great strides have been made in discovering common genes influencing the susceptibility to common diseases, such as diabetes, Crohn’s disease and schizophrenia. However, no genes have yet been convincingly associated with migraine susceptibility, probably due to the high degree of variability of the disease phenotype combined with the lack of viable laboratory tests.
”To address this problem, we developed a new analysis technique concentrating on different symptoms of migraine”, says Professor Aarno Palotie (University of Helsinki, Finland, and the Sanger Institute, Cambridge, UK). The new technique was used in the large international study including 1700 migraine patients and their close relatives from 210 Finnish and Australian migraine families. The Finnish families had been ascertained through neurology clinics, while the Australian families had been collected through a twin study. An initial genome-wide microsatellite study was followed up by an independent targeted replication study.
Researchers identified one gene locus on chromosome 10q23, which showed significant evidence of genetic linkage in both populations studied as well as in the replication study. The gene locus was especially strongly linked to female migraineurs. “In a further analysis, two independent previous studies, one Finnish and one Australian, had detected the same locus, but in those studies the level of evidence had been just below significance, and thus the connection had so far been missed”, tells researcher Verneri Anttila from Palotie’s group.