That environmental factors have a huge impact on people with migraine is undeniable, both in terms of their importance in triggering acute attacks and their impact on the course of the disorder throughout a person's life.

Trigger factors from the internal environment (for example, gonadal hormonal fluctuations, changes in blood glucose with fasting) as well as from the external environment (for example, changes in barometric pressure, environmental stress, exposure to exogenous chemicals such as nitric oxide, histamine, or other chemicals in foods or food additives) are well-known modulators of migraine. How these environmental factors impact migraine remains unknown.

There is increasing evidence that environmental factors may actually impact people at a basic cellular level through what are known as epigenetic effects on the DNA. These include adding a methyl CH3 group (epigenetic methylation) to the DNA, the basic instruction set for cellular activity and alterations of the winding pattern of DNA around histone proteins inside the cell nucleus. Both of these alterations, which can be caused by environmental exposures, may result in altered expression of the DNA and subsequent changes in activity of the cells within the brain. This new emerging field, thus far unexplored in people with migraine, promises to begin to explain how the environment affects the course of migraine in an individual.

Mayo investigators are uniquely well-positioned for future epigenetic studies because of Mayo's large library of genomic DNA linked to detailed clinical phenotypic information stored as elemental data.