Affecting more than 5 million Americans, fibromyalgia is the most commonly diagnosed chronic pain disorder today. But is fibromyalgia hereditary?

Well, that question is more complicated than it may seem. A relatively newly recognized disorder, with its modern definition and diagnosis being solidified in 1972 by Dr. Hugh Smythe, and only seen as an actual condition by the American Medical Association (AMA) in 1987, there haven’t been as many opportunities (or enough funding) to study fibromyalgia as there have been with other conditions and disorders.

So what does this mean for sufferers of fibromyalgia? What does modern science say about the possibility of passing on fibromyalgia to your children/grandchildren?

What causes fibromyalgia?

According to the American College of Rheumatology:

There is most often some triggering factor that sets off fibromyalgia. It may be spine problems, arthritis, injury, or other type of physical stress. Emotional stress also may trigger this illness. The result is a change in the way the body “talks” with the spinal cord and brain. Levels of brain chemicals and proteins may change. More recently, Fibromyalgia has been described as Central Pain Amplification disorder, meaning the volume of pain sensation in the brain is turned up too high.

With such a broad description of the possible causes of fibromyalgia, it is clear that the disorder is not very well understood, even by medical professionals. But even when this is the case, there have been some breakthroughs in the study of whether or not we can answer “is fibromyalgia hereditary.”

Is fibromyalgia hereditary?

Like many other rheumatic diseases, fibromyalgia is believed to be the result of a genetic tendency that could be passed down to one’s genetic offspring, especially from mothers to daughters.

Defined as possibly being “epigenetic,” rheumatic diseases could be a result of specific genes being “turned on” by environmental factors that otherwise might stay dormant.

A quick breakdown on the phenomenon of epigenetics from The Guardian reads:

Epigenetics is essentially additional information layered on top of the sequence of letters (strings of molecules called A, C, G, and T) that makes up DNA.

If you consider a DNA sequence as the text of an instruction manual that explains how to make a human body, epigenetics is as if someone’s taken a pack of highlighters and used different colours to mark up different parts of the text in different ways. For example, someone might use a pink highlighter to mark parts of the text that need to be read the most carefully, and a blue highlighter to mark parts that aren’t as important.

There are different types of epigenetic marks, and each one tells the proteins in the cell to process those parts of the DNA in certain ways. For example, DNA can be tagged with tiny molecules called methyl groups that stick to some of its C letters. Other tags can be added to proteins called histones that are closely associated with DNA. There are proteins that specifically seek out and bind to these methylated areas, and shut it down so that the genes in that region are inactivated in that cell. So methylation is like a blue highlighter telling the cell “you don’t need to know about this section right now.”

So what does this all mean? Does this necessarily mean that fibromyalgia is hereditarily passed?

As of right now, the only answer that science can give to the question, “Is fibromyalgia hereditary?” is that it very well possibly could be. Without more study, peer-reviewed research, and funding, we simply don’t know more than the simple fact that fibromyalgia seems to cluster in family lines with no real pattern or ease of diagnosis.

For more information on fibromyalgia, please visit the American College of Rheumatology.