Its most notable characteristic is pain. Other symptoms include fatigue, sleep disorders, headaches, migraines and irritable bowel. Also, it affects mostly women: They make up 75 to 90 percent of the 10 million people who suffer from it in the U.S. And despite federal approval in recent years of several medications to treat it, researchers still don’t know what causes fibromyalgia.
A recent study may shed some light, however.
|John Shively (Photo by Darrin S. Joy)|
Researchers led at City of Hope by John Shively, Ph.D., chair of the Department of Immunology, and Steve Sommer, M.D., Ph.D., found a link between fibromyalgia and a gene called MEFV.
Scientists know that mutations in MEFV are connected to another disease called familial Mediterranean fever. The disorder shares many symptoms with fibromyalgia, so the researchers thought MEFV might share a connection to fibromyalgia, as well.
Using blood samples from 100 patients with fibromyalgia and their parents, the scientists scanned the MEFV gene for mutations. In 15 percent of the patients, they found 10 sets of rare genetic changes that were inherited from their parents too frequently to be random chance.
“Since the mutations are rare, it is unlikely they would be transmitted from parent to child at a frequency greater than 50-50 unless they were associated with disease,” said Shively. “More likely, they are closely linked to the disease and therefore handed down from parent to child.”
While other researchers have found evidence that fibromyalgia can be inherited, the current study provides a concrete link to specific mutations in a gene. The finding could one day open the door to genetic testing, helping fibromyalgia patients’ family members judge their risk of the disease.
In addition to uncovering a possible genetic link, the study also provides more evidence that the immune system plays a part in fibromyalgia.
The scientists found that families with any of the 10 sets of mutations in the MEFV gene had higher levels of an immune system protein called interleukin-1 beta, or IL-1B. Researchers believe IL-1B causes some of the symptoms of familial Mediterranean fever.
The researchers hope to study other genes involved in inflammation in the fibromyalgia patients to further test their idea that the disorder is linked to the immune system, according to Shively.