Scientists are moving closer to predicting who may develop dangerous heart rhythm problems years before symptoms begin.
In a new study published in Nature Communications, researchers led by Penn State College of Medicine found that both rare and common genetic changes work together to increase the risk of early atrial fibrillation.
AFib develops when the heart’s upper chambers lose their normal rhythm. Instead of beating in an organized pattern, they shake rapidly, making it easier for blood clots to form. If a clot travels to the brain, it can cause a stroke, which is sometimes the first sign that a person has AFib.
While aging remains the biggest cause of AFib, about one in five cases has a genetic component. Some families inherit rare mutations that dramatically raise their risk, but these mutations do not affect everyone equally. The new research helps explain why.
The investigators studied a rare mutation in the LMNA gene together with thousands of small genetic variations that are common throughout the population. Individually, these common variations have very small effects. However, when many occur together, they appear to increase the impact of the rare mutation.
Using advanced laboratory models created from human blood samples, the researchers observed how these genetic factors altered DNA organization inside heart cells. The changes disrupted genes involved in the electrical system that keeps the heartbeat regular, including pathways controlling sodium flow into cells.
To confirm their findings, the team analyzed data from the UK Biobank, which contains health and genetic information from more than half a million participants. People carrying a larger number of common risk variants were much more likely to develop AFib at younger ages when they also carried a rare mutation.
The study suggests that doctors may eventually need to consider a person’s complete genetic profile rather than searching for only one harmful mutation. This could improve estimates of who is most likely to develop AFib early in life.
The researchers also believe the LMNA gene should receive greater attention during genetic testing for inherited heart rhythm disorders. Some people with LMNA variants may first develop AFib before showing signs of other heart diseases, creating an opportunity for earlier diagnosis and monitoring.
This research does not immediately change medical practice because it was performed mainly in laboratory cell models supported by population genetic data. Nevertheless, it offers a strong scientific explanation for how multiple genetic factors combine to influence AFib risk.
Future patient studies could help transform prevention by identifying high-risk individuals early enough to prevent strokes through monitoring and timely treatment.
If you care about heart health, please read studies about top foods to love for a stronger heart, and why oranges may help fight obesity, diabetes, and heart disease.
For more health information, please see recent studies about simple guide to a 7-day diabetes meal plan, and why you should add black beans to your plate.
Source: Penn State College of Medicine.
