New Study Identifies Profile of Long Covid in Blood DNA

Ariel Jaitovich, MD

A study led by Albany Medical Center researchers has shown that the blood DNA methylation levels of long Covid patients differ from those of healthy patients, and that long Covid patients share the same blood biomarkers even when they have different symptoms.

“This suggests that long Covid is a single disease and not an aggregation of multiple conditions,” said pulmonologist Ariel Jaitovich, MD, the study’s corresponding author and an associate professor in the Departments of Medicine and Molecular and Cellular Physiology at Albany Medical College.

According to the CDC, millions of U.S. adults and children have been affected by long Covid, which follows a Covid-19 infection and is present for at least three months. It’s characterized by an array of lingering symptoms, including shortness of breath, cough, fatigue or exhaustion, racing heart, chest pain, brain fog, an inability to concentrate, or a general feeling of malaise.

In the study, blood samples were collected between February 2021 and June 2021 from 103 patients with long Covid at Albany Medical Center’s pulmonary clinic. Additional samples were collected from healthy volunteers and from patients who previously tested positive for Covid-19 but did not experience lingering symptoms.

In collaboration with scientists from the University of Wisconsin–Madison and Temple University, the researchers isolated DNA from the blood samples and performed whole genome methylation sequencing. Then, RNA was extracted and a differential methylation analysis was performed, followed by complex bioinformatics analyses and statistical comparisons.

The researchers found that patients with post-acute sequelae of Covid-19 (long Covid) have a different blood DNA methylation profile than healthy patients and those who previously had a Covid-19 infection but didn’t develop long Covid.

Dr. Jaitovich added that while additional, wider studies are needed, identifying the blood DNA methylation levels of long Covid could facilitate the diagnosis of long Covid, gauge its severity, and aid in treatment monitoring for patients who have the disease. Ultimately, it could also open the door to the development of a blood test to diagnose long Covid.

Titled, “Blood DNA methylation in post-acute sequelae of COVID-19 (PASC): a prospective cohort study,” the paper was published in the August 2024 issue of eBioMedicine, a peer-reviewed, open access medical journal published by The Lancet Group.