BETHESDA, Md., Feb. 4 (UPI) -- Scientists identified a genetic mutation responsible for triggering hives as an allergic reaction to vibration, according to new research from the National Institutes of Health.
Hives caused by vibration, known as vibratory urticaria, occurs when mast cells, which release inflammatory chemicals as part of an immune system response, react to vibration, NIH researchers found in the study.
Vibration from towel drying, clapping, or riding in a vehicle on a bumpy road can cause mast cells to release histamine, tryptase and other chemicals into the bloodstream, triggering hives and other allergic symptoms.
"Notably, we also observed a small increase in blood histamine levels and a slight release of tryptase from mast cells in the skin of unaffected individuals exposed to vibration," Dr. Hirsh Komarow, an allergic diseases researcher at the National Institute of Allergy and Infectious Diseases, said in a press release. "This suggests that a normal response to vibration, which does not cause symptoms in most people, is exaggerated in our patients with this inherited form of vibratory urticaria."
To identify the condition's genetic cause, researchers involved with the study, published in the New England Journal of Medicine, sequenced and compared DNA samples on 36 members of three families, some of whom have the condition.
Among family members with the condition, researchers found a mutation in the ADGRE2 gene that was not present in family members without the condition or more than 1,000 other people with a similar genetic ancestry who also didn't have it.
"Investigating rare disorders such as vibratory urticaria can yield important insights into how the immune system functions and how it reacts to certain triggers to produce allergy symptoms, which can range from mild to debilitating," said Dr. Anthony Fauci, director of the NIAID. "The findings from this study uncover intriguing new facets of mast cell biology, adding to our knowledge of how allergic responses occur."