New genetic risk variants identified for restless legs syndrome
Around ten percent of Germans are affected by the so-called Restless Legs Syndrome (RLS). The causes of the restless, restless or restless legs are largely unknown. However, researchers have now discovered new genetic risk variants for RLS.
Strong urge to move at night
Patients with Restless Legs Syndrome (RLS) experience a strong urge to move at night and suffer from unpleasant sensations such as pain or tingling in the legs. Up to ten percent of the European population is affected, including many children. The causes are largely unknown. However, an international team has now discovered new genetic risk variants.
Pain and tingling in the legs
With RLS, the symptoms occur when the body comes to rest. "As a rule, this is in the evening and at night when there is a noticeable pulling, tearing or tingling in the legs," writes the German Restless Legs Association on its website.
"RLS patients mostly describe these complaints and misperceptions quite differently. They can appear on one side, on both sides or alternately on one side or the other, ”the experts continued.
However, many sufferers struggle not only with the actual symptoms, but also with the consequences such as sleep disorders, depression or anxiety. In severe cases, those affected have to take medication all their lives.
Little is known about the causes of the disease
Little is known about the molecular causes and the exact disease mechanisms.
Prof. Juliane Winkelmann, Professor of Neurogenetics at the Technical University of Munich (TUM) and Head of the Institute for Neurogenomics at the Helmholtz Center Munich, has been researching this neurological disease with her team for over ten years.
She and her team have already shown that it also has genetic causes. With international partners from the British Cambridge University and the US company "23andMe", it has now carried out the world's largest study on the basis of 45,000 patients, according to a statement.
"We were able to identify a total of 19 risk-associated variants in the genetic makeup of the study participants - 13 of which are new," explained Dr. Barbara Schormair from the Institute for Neurogenomics at the Helmholtz Zentrum München, one of the first authors of the study, which was recently published in the specialist journal "The Lancet Neurology".
"We are convinced that our results will significantly advance our understanding of the molecular causes of restless legs syndrome," said the expert.
Congenital peculiarities of the nervous system
Risk-associated variants are specific peculiarities of the genetic molecule, i.e. the sequence of letters in the DNA, which occur more frequently in those affected than in those not affected.
Genes that are related to the development of the disease are located at or near these variants.
The international team compared the genetic data of 15,000 patients with that of 95,000 individuals from the general population.
The results were then confirmed in another study with 31,000 new patient records and over 280,000 control records.
In addition, the researchers examined which biological processes are most closely associated with the risk variants and discovered surprising things:
In particular, genes that are involved in the embryonic development of the nervous system appeared in this study, even though the disease usually only occurs in later decades.
"This suggests that innate peculiarities of the nervous system only become apparent later in the form of the Restless Legs Syndrome. Now that we understand this better, we can also think about suitable therapies, ”said Prof. Winkelmann.
"Our genetic study takes us a big step forward in finding new and better drugs for our patients," said the expert.
Dangerous drug as a therapy option
According to the study team, thalidomide could be a possible therapy option - but with restrictions. The drug affects a cellular process that, according to the new study, could also play a role in restless legs syndrome.
In the past, the drug was used under the brand name Contergan as a sleeping pill during pregnancy, but has led to serious malformations in unborn children. The victims are still suffering from the consequential damage.
Today the substance is used against certain cancers.
According to the team of scientists, a possible use for the therapy of restless legs syndrome in male patients who cannot be treated otherwise after their fertile phase can only be decided after careful clinical studies. (ad)