What are the genetic changes related to restless legs syndrome ?
Restless legs syndrome likely results from a combination of genetic and environmental factors, many of which are unknown.  Studies suggest that restless legs syndrome is related to a shortage (deficiency) of iron in certain parts of the brain. Iron is involved in several critical activities in brain cells, including the production of a chemical messenger (neurotransmitter) called dopamine. Among its many functions, dopamine triggers signals within the nervous system that help the brain control physical movement. Researchers believe that malfunction of the dopamine signaling system may underlie the abnormal movements in people with restless legs syndrome. However, it is unclear how iron deficiency is related to abnormal dopamine signaling, or how these changes in the brain lead to the particular signs and symptoms of the condition.  Variations in several genes have been studied as risk factors for restless legs syndrome. Most of these genes are thought to be involved in the development of nerve cells (neurons) before birth. It is unclear whether any of the genes play roles in brain iron levels or in dopamine signaling. Variations in known genes appear to account for only a small percentage of the risk of developing restless legs syndrome. Changes in other genes, which have not been identified, probably also contribute to this complex disorder. Researchers suspect that the early-onset form of restless legs syndrome is more likely than the late-onset form to have a genetic basis.  Nongenetic factors are also thought to play a role in restless legs syndrome. For example, several other disorders increase the risk of developing the condition. These include a life-threatening failure of kidney function called end-stage renal disease, diabetes mellitus, multiple sclerosis, rheumatoid arthritis, and Parkinson disease. People with low iron levels associated with a shortage of red blood cells (anemia) and women who are pregnant are also more likely to develop restless legs syndrome. In these cases, the condition usually improves or goes away when iron levels increase or after the woman gives birth.  Restless legs syndrome can be triggered by medications, including certain drugs used to treat nausea, depression and other mental health disorders, colds and allergies, heart problems, and high blood pressure. Use of caffeine, nicotine, or alcohol can also trigger restless legs syndrome or make the signs and symptoms worse. In these cases, the condition usually improves or goes away once a person stops using these medications or substances.