The genetic causes of Raynaud’s phenomenon have been identified for the first time, researchers have announced.
Researchers at Queen Mary University of London’s Precision Healthcare University Research Institute (PHURI), UK, and the Berlin Institute of Health (BIH) at Charité – Universitätsmedizin Berlin, Germany, carried out the largest genetic study into the condition.
Using electronic health records from the UK Biobank, they identified more than 5,000 people affected by Raynaud’s. The team also used electronic health records from Queen Mary’s Genes & Health study.
Although between 2% and 5% of the population are affected by Raynaud’s, it is under-investigated and little is understood about the genetic cause. There are also limited treatments.
The findings are published in Nature Communications.
Researchers led by Professor Claudia Langenberg and Professor Maik Pietzner, working across PHURI and the BIH, discovered variation in two genes that predisposed participants to Raynaud’s phenomenon: the alpha-2A-adrenergic receptor for adrenaline, ADRA2A, a classic stress receptor that causes the small blood vessels to contract. This gene is the transcription factor IRX1, which may regulate the ability of blood vessels to dilate.
“This makes sense when it’s cold or dangerous, because the body has to supply the inside of the body with blood,” said Prof Pietzner.
“In Raynaud’s patients, this receptor seemed to be particularly active, which could explain the vasospasms, especially in combination with the second gene that we found.
“If its production is increased, it may activate genes that prevent constricted vessels from relaxing as they would normally do. Together with the overactive adrenaline receptor, this may then lead to the vessels not suppling enough blood for a longer period of time, which leads to the observed white fingers and toes.”
The researchers replicated some of their findings using data from participants of British Bangladeshi and Pakistani origin from Queen Mary’s Genes & Health study.
The researchers’ findings help to understand, for the first time, why the small vessels react so strongly in patients, even apparently without exposure to cold.
Dr Emma Blamont, head of research for Scleroderma and Raynaud’s UK (SRUK), said: “Raynaud’s is a painful, chronic condition that affects around one in six people in the UK. We know that attacks can be brought on by certain triggers like cold and stress, but relatively little is known about why some people experience Raynaud’s and others don’t.
“For the millions of people living with this condition, simple everyday tasks can be a challenge, so research like this, which significantly advances our understanding of Raynaud’s and the role that genetics may play in causing it, is crucial.
“The next step is to confirm these important findings in more diverse population groups and validate the results through functional studies. If successful, these findings could help us unlock more new therapeutic avenues for Raynaud’s leading to better, more targeted and kinder treatments.”
The findings could lead to recommendations for patients to help manage the condition or its symptoms.
Hartmann S, Pietzner M, Langenberg C. ADRA2A and IRX1 are putative risk genes for Raynaud’s phenomenon. Nature Communications 12 October 2023.
Leave a Reply