More than a billion people worldwide suffer from migraines, and although this condition is common, scientists do not yet understand the full mechanism of how people develop it.

Migraine is believed to be a neurovascular disorder with pathological mechanisms within the brain and blood vessels of the head.

Previous research has shown that genetic factors contribute significantly to the risk of migraine headaches.

However, it has long been debated whether the two main types of migraine – migraine with aura and migraine without aura – share the same genetic background.

A recent study published in Nature Genetics notes that there are 123 genetic regions associated with migraine risk, some of which can be targeted with drugs.

The researchers found genetic differences between the two main types of migraine: those with migraine with aura (or aura, also known as classic migraine) and migraine without aura.

Aura is described as a category of symptoms that occur during a migraine and can last up to an hour. Common visual symptoms include seeing flashes, dark spots, or even temporary blindness.

Other symptoms may include physical numbness or difficulties speaking.

The results of the analysis showed that there are common factors that increase the risk of migraine, regardless of its type, and risk factors specific to each type (migraine with aura or without aura).

“In addition to implicating dozens of new regions of the genome for a more targeted investigation, our study provides the first meaningful opportunity to assess common and distinct genetic components in the two major subtypes of migraine,” explained the study’s lead author, first Heidi Hautkangas.

Two of the 123 genetic regions correspond to proteins targeted by migraine drugs.

An expanded list of migraine genetic regions may allow the identification of new drugs that target these types.

One of the newly identified regions contains genes (CALCA/CALCB) that encode a peptide associated with the calcitonin gene, a molecule implicated in migraine attacks and blocked by CGRP-inhibiting migraine drugs. Another risk area covers the HTR1F receptor gene, which encodes serotonin 1F, which is also a target of new migraine drugs.

Dr Matti Pirinen, study leader from the Institute of Molecular Medicine in Finland, University of Helsinki commented: ‘These two new associations near genes already targeted by potent migraine drugs suggest that there may be other potential drug targets among the new genetic regions, and provide a clear rationale. For future genetic studies with larger sample sizes.”

Migraine auras are caused by a phenomenon called cortical proliferation depression. It is an electrical wave propagating from the occipital lobe responsible for visual processing.

This may be why visual disturbances are among the most common migraine symptoms.

Migraine auras appear in about a third of patients.

It is noteworthy that this study was a joint effort between research groups from Australia, Denmark, Estonia, Finland, Germany, Iceland, the Netherlands, Norway, Sweden, the United Kingdom and the United States of America.