SPAIN – An international consortium of scientists has identified 38 genetic variants that can cause migraine, 28 of them completely new.  This is the major finding of the causes of this disease conducted to date.

The results of the study, conducted by researchers at centers in Spain, United States, Norway, Finland, Denmark or Germany, have been published in Nature Genetics.

In the study, the genome of 375,000 individuals in the United States, Australia and Europe; 59,674 of them were had migraine while the rest were controls.

Migraine is a disorder that affects one billion people worldwide (15-20% of the world population), mostly women.

This disorder, highly disabling, causing headaches, nausea, vomiting and sensitivity to light and noise, and in the most severe cases causes temporary paralysis of half body.

Despite it being common, every seven people in the world suffer from it, the causes of migraine are still unknown according to Ester Cuenca-Leon, one of the researchers and biologist from Research Institute of Vall d’Hebron Hospital in Barcelona.

He said that the study is important because it will help to complete the genetic map of the different forms of migraine, to define the genetic mechanisms underlying this disorder, and find treatments to combat the causes, not just the symptoms.

So far they had identified some genetic variants (alterations in a letter of a gene) forms of rare migraine, those produced by mutation of a single gene and are found “in less than one person in a thousand” according to Cormand Bru, researcher at the University of Barcelona and member of the International Consortium for Genetics of Migraines. He said that this is the case of hemiplegic migraine, for example, which causes paralysis of half the body and is caused by a single gene in each family.

In the case of common migraine, however, the genetic map of this disease is much more varied. Common migraine has a complex and polygenic genetic basis, i.e. one must have several altered genes. It is the sum of each of these changes which ultimately leads to migraine, according to Cormand.

In fact, the researcher adds, “it is possible that the full genetic landscape of migraine contains more than one hundred genes.”

Thanks to the huge sample of this study (375,000 individuals), researchers have been able to perform a meta-analysis has identified 38 genetic variants associated with migraine, 28 of which had not been described before, and twelve were discovered in several previous works.

The study is important because it reopens the debate on whether this disease is neuronal or vascular, because “most of the genes have now found in common migraine regulate the vascular system, while in the most severe and rare forms damage first it is in the brain,” as explained by Cuenca-Leon.

And for the first time, the study determined that the genes that cause common migraine and predisposing the rarest forms of this disease “are completely different,” said Cormand.

The work will not only help to better understand the origin of migraine, but will be useful for the medium term, more personalized treatments and appropriate to the patient, both researchers agree.