Could going abroad reduce your risk of migraines?

Over the last few weeks, we’ve had a sudden burst of sunshine here at Warwick, making it simultaneously easier and more difficult to focus on revision during exam season. While I for one am definitely not complaining about a surge in Vitamin D, there is always an element of surprise when we get a spell of good weather. As well as being unfortunately subjected to grey and dreary skies for most of the year, according to new research being unaccustomed to warm weather could also increase our risk of developing a migraine.

Researchers including Aida Andrés from University College London (UCL), and Felix Key from the Max Planck Institute for Evolutionary Anthropology in Leipzig, have studied the gene that codes for the protein TRPM8. The transient receptor potential cation channel subfamily M member 8 (TRPM8), catchy name, I know, is a protein encoded by the TRPM8 gene. Also known as the cold and menthol receptor 1 (CMR1), the TRPM8 channel is the primary molecular transducer of the ‘cold’ sensation felt by humans.

While I for one am definitely not complaining about a surge in Vitamin D, there is always an element of surprise when we get a spell of good weather

The gene for this particular comes in two ‘flavours’. The older variant is one humans share with chimpanzees, and is commonly found in those living in hotter climates such as Africa. The newer variant is more prevalent in people living in northern, or European. By screening population of genetic data from Africa, Europe and South East Asia, the researchers were able to find a correlation between the frequency of each gene and global latitude.

For example, the new variant of the gene was found in around 88 per cent of Finnish people, but only 5 per cent of Nigerians. Using computer simulations, it was hypothesised that the newer variant of TRPM8 evolved in Africa, before migration to other continents occurred. Mark Shriver from Penn State University stated: “This is probably the first time [the adaptation of] a sensory gene has been tied to environment.

By screening population of genetic data from Africa, Europe and South East Asia, the researchers were able to find a correlation between the frequency of each gene and global latitude

This discovery is significant because the TRPM8 has been linked to migraines, with the older variant protecting against the ailment. Conversely, the newer variant is thought to increase the risk of experiencing migraines. “We know the prevalence of migraine is lower in African Americans,” says Key. While it isn’t clear why the sensations of cold facilitated by TRPM8 can cause migraines, many people do suffer from cold-triggered headaches.

It is also unclear why a gene variant that increases the prevalence of migraines would be useful, as I’m sure anyone who has ever suffered with one would agree! It seems that any increased risk of migraine that comes with being better adapted to live in colder climates is simply a less than welcome side effect. Migraines are complex, and it is likely that many gene variants other than TRPM8 can contribute to a person’s chance of being more susceptible to them. Nevertheless, these findings are still important evidence that humans have evolved over the last 100,000 years, said Rasmus Nielsen at University of California, Berkeley.