Another Genetic Link to Migraine?

Researchers at the University of California have discovered a new genetic link to migraine – and a rare sleep disorder – that may get us closer to the cause of migraine than ever before.

First, a note.  Last week on Facebook, Damien Higgins posted the following:  There was Migraine News today that made many of the international news channels and you havnt even mentioned it!!! this page is not exactly on the ball, is it!!!http://news.sky.com/story/1085914/hope-for-migraine-sufferers-after-genes-find

Well, I have no particular excuse for not mentioning this story sooner, other than to say that this website has not yet reached the level of perfection that I or Damien may want!

That being said, many stories hit “international news” and are really hardly worth mentioning, in my opinion.  Honestly, a lot of migraine news is old news, poorly reported, blown out of proportion, or in reality not useful.  And sometimes it’s worth taking the extra time to research the news a little more before repeating the same thing here.

Regarding genetics and migraine, we’ve discussed a lot of discoveries here.  In fact, back in 2010 we talked about a similar news story – Found: Genetic Link to “Basic” Migraine

We’ve also talked about something critical to understand – Migraine: Why Genetic Studies haven’t Solved all our Problems.

In Damien’s defence, however, this news story is worth mentioning.  And I won’t claim that the Sky news report is overblown, although most migraineurs are probably tired of seeing the same old headline – “Hope for Migraine Sufferers…”! 🙂

Study Overview

First, we need to be cautious about claiming that we’ve “finally found the genetic cause of common migraine”.  This is not the first time genetic mutations have been linked with common forms of migraine.  There are some unique things about this study which we’ll discuss in a moment, but it’s a tricky thing to prove that a genetic mutation is the cause or even related to “most” migraine attacks.

Researchers were actually looking at two conditions: Migraine and Advanced Sleep Phase Syndrome.  This sleep syndrome causes you to go to sleep earlier (ie in the evening) and get up earlier (ie between 1 and 5 am).

Researchers found two families in which many members had both conditions (in this case, the sleep disorder would be called familial advanced sleep phase syndrome).

To make a long story short, it was discovered that two related gene mutations were highly associated with both conditions.

Now mice who had one of these mutations (CKIδ-T44A) were also researched.  These mice had a lower threshold for cortical spreading depression (CSD), a storm that sweeps across the brain that is considered a key part of the migraine chain reaction.  In other words, they were more likely to get CSD.

These mice were more sensitive to pain, and astrocytes (certain neurological cells) showed increased calcium signalling, which may relate to parts of the migraine reaction as well.

Now the research on CKIδ-T44A and the mice and migraine is not new.  Neither is the link between these two mutations and advanced sleep phase syndrome.  However, the link with the two mutations and the two conditions – migraine and advanced sleep phase syndrome is.

You might be a little underwhelmed that we’re just talking about two families, and a rare sleep disorder, and just another two mutations after we’ve already linked others with migraine.

However, this is how a lot of good research starts.

These mutations are linked.  And the most important finding may not be the mutations themselves, but what they point to.

For one thing, they both influence a special protein known a connexin 43 (Cx43).  Even if these particular genetic mutations don’t turn out to be common in migraineurs, there could be other factors that are impacting Cx43, and so that might be the direction that future research takes.

I’ve intentionally avoided getting into all the specific mechanisms of these mutations in order to focus on the practical implications.  But if you’re interested in the more technical aspects, you can read the study abstract:  Casein Kinase Iδ Mutations in Familial Migraine and Advanced Sleep Phase and a discussion of the findings at Gene Mutations Tied to Migraine, Sleep Disorder.