The International Consortium for Cluster Headache Genetics (CCG) is a global collaboration to uncover the genetic basis of cluster headache and other rare headache disorders
Cluster headache is a neurological disorder characterized by attacks of extremely intense headaches on one side of the head, often behind one eye. Attacks typically last between 15 minutes and 3 hours and are associated with a red, teary eye, a small pupil, a runny nose or other so called “trigeminal autonomic symptoms” on the same side as the headache. Attacks often occur in clusters over weeks to months, with attack-free periods between; hence the term ‘cluster headache’. In 10-15% of patients cluster periods never remit for longer than three months, classifying them as having chronic cluster headache. Cluster headache is two times more prevalent in men than in women and is estimated to have a world-wide prevalence of 1 in 1000.
While effective treatment exists, up to 10-20% of patients have little benefit from standard treatment. Development of better treatment is hampered by lack of knowledge of the underlying molecular mechanisms of cluster headache.
Cluster headache is believed to be partially genetic. The most effective approach to identify genetic factors for complex disorders thus far are genome-wide association studies (GWAS), which examine several million genetic variants spread over the genome. GWAS require genetic data form a large number of persons with cluster headache and from healthy controls. We hope that unravelling the genetic basis of cluster headache will shed light on the biological mechanisms causing the disease.