Researchers from the Precision Healthcare University Research Institute (PHURI) at Queen Mary University of London and the Berlin Institute of Health (BIH) at Charité – Universitätsmedizin Berlin have identified the genetic causes of Raynaud’s phenomenon. Their findings, published today (October 12) in Natural Communications could lead to the first effective treatments for people with Raynaud’s disease.
Raynaud’s phenomenon (RP) is an inherited disease that affects blood circulation. It is a vasospastic condition, meaning that small blood vessels near the surface of the skin spasm which can restrict blood flow. People with Raynaud’s syndrome often experience pain in their fingers and toes, often accompanied by changes in the color of their skin, due to a lack of blood flow during attacks when they are cold or emotionally stressed. In more severe cases, it can cause severe pain or ulcers.
Around 2 to 5% of the population is affected by Raynaud’s disease. Although it is a common disease, it is understudied and little is known about the genetic cause of the disease.
There are limited treatments available for RP. Doctors usually advise the patient to use “self-management” strategies, such as staying warm and avoiding attack triggers. In severe cases, medication may be prescribed. These are “recycled drugs”, usually drugs intended to lower high blood pressure. These often cause serious side effects in patients. A better understanding of the genetic mechanisms underlying Alzheimer’s disease is necessary to develop safe and effective treatments.
Researchers led by Professor Claudia Langenberg and Professor Maik Pietzner, working at PHURI and BIH, have carried out the largest genetic study of Raynaud’s phenomenon. The team used electronic health records from the UK Biobank, a large-scale biomedical database and research resource containing genetic and health information from half a million UK participants, to identify more than 5 000 people affected by Raynaud’s disease. The team also used electronic health records from Queen Mary’s Genes and Health study.
The results
The researchers discovered variation in two genes predisposing participants to Raynaud’s phenomenon: one was the alpha-2A-adrenergic receptor for adrenaline, ADRA2A, a classic stress receptor that causes small blood vessels to contract.
“This makes sense when it is cold or dangerous, because the body has to supply the inside of the body with blood,” explains Maik Pietzner, professor of health data modeling at PHURI and group leader at BIH.
“In Raynaud patients, this receptor seemed particularly active, which could explain the vasospasms, particularly in association with the second gene that we found: this gene is the transcription factor IRX1 which can regulate the ability of blood vessels to dilate.
“If its production increases, it can activate genes that prevent constricted vessels from relaxing as they normally would. In combination with the overactivity of the adrenaline receptor, this can then lead to the vessels not supplying enough blood for a longer period of time, leading to the white fingers and toes seen.
The researchers replicated some of their findings using data from participants of British Bangladeshi and Pakistani descent from Queen Mary’s. Genes and health study.
The researchers’ findings help to understand, for the first time, why small vessels react so strongly in patients, even apparently without external stimuli, such as exposure to cold.
Mr Emma Blamont, Head of Research for Scleroderma and Raynaud’s UK (SRUK), said:
“Raynaud’s disease is a chronic, painful condition that affects around one in six people in the UK. We know that seizures can be caused by certain triggers like cold and stress, but relatively little is known about why some people have Raynaud’s and others.” t. For the millions of people living with the disease, simple daily tasks can be a challenge, which is why research like this, which significantly advances our understanding of Raynaud’s disease and the role genetics may play in its appearance, are crucial.
“The next step is to confirm these important results in more diverse population groups and to validate the results with functional studies. If successful, these results could help us unlock more new therapeutic avenues for Raynaud’s disease, leading to better, more targeted and gentler treatments. »
The results could lead to recommendations for patients to help them manage the disease or its symptoms. For example, researchers have shown that people with a genetic predisposition to low blood sugar are at increased risk of Raynaud’s syndrome, suggesting that patients should possibly avoid longer episodes of hypoglycemia.
For Claudia Langenberg, director of PHURI and professor of computational medicine at BIH, this study illustrates that the integration of genomic data and electronic health records can quickly help to better understand diseases whose etiology remains unknown. She says:
“Of course, we hope that our discoveries will ultimately lead to new treatment options. There are already approved drugs that more or less specifically inhibit ADRA2A function, such as the antidepressant mirtazapine, and our results suggest that they may present alternative treatment options for patients suffering from the symptoms of Raynaud’s disease.
This article is originally published on nouvelles-du-monde.com
