A group of researchers concludes that a gene variant commonly linked to migraines may have spread because early humans needed it to thrive amid cold climates.
The World Health Organization estimates that a migraine is one of the common headache disorders suffered by one in every seven adults in the world. The organization noted that for some unknown reason, the condition appears less common in the Far East region consisting of East Asia, Russian Far East, and Southeast Asia.
The recent study, headed by Felix Key of the Max Planck Institute for Evolutionary Anthropology, noted that a migraine is highest in individuals of European descent. This is also the population that possesses the highest frequency of the TRPM8, the gene that helps humans adapt to a cold environment.
TRPM8 gene is also associated with a variant, which in return, is commonly attributed to migraines.
Early Human Population
The researchers noted that ancient population migrated from Africa to colder locations in Asia, Europe, and other parts of the world within the last 50,000 years.
"This colonization could have been accompanied by genetic adaptations that helped early humans respond to cold temperatures," explains Aida Andres, who supervised the study published in the journal PLOS Genetics.
Key and his team suspected that this particular adaptation to the freezing environment may have added to the factors that made migraines prevalent in a particular group of the population. To support this hypothesis, the team examined the TRPM8, a gene that allows people to detect and respond to cold temperatures.
Their analysis revealed that a genetic variant upstream from the TRPM8 developed progressively more common in people living in higher altitudes during the last 25,000 years. This detail remains observable at present with the gene variant commonly carried by people living in higher altitudes and with a colder environment.
Interestingly, only 5 percent of people with Nigerian descent possess the gene variant while 88 percent of those with Finnish lineage carry the trait.
"This study nicely shows how past evolutionary pressures can influence present-day phenotypes," Key highlights.
What Triggers Migraine
WHO says that a migraine is three times more common in women than in men, probably due to hormonal factors. While the condition mostly affects those aged between 35 and 45, it can also affect children.
According to the American Migraine Foundation, storms, excessive heat, and changes to barometric pressure are also common causes of a migraine.
The condition might also be triggered by stress with one recent study showing that 50 to 70 percent of people with migraines showed a correlation between daily stress and frequent attacks.
A migraine can also be triggered by irregular sleep, caffeine and alcohol consumption, as well as food containing histamine and MSG.
Chocolate, cheese, artificial sweeteners, and cured meats also commonly trigger migraines, as well as dehydration, medication overuse, perfumes, food with strong smells, and the stench of chemicals, and gasoline.