Investigators explore factors that increase susceptibility to COVID-19

Investigators in the Department of Computational Biomedicine at Cedars-Sinai wanted to find out which factors most influenced susceptibility to COVID-19 infection and disease severity. Was it genetics? Or was it the family environment, that is, the germs that circulate in your daily life?

Their conclusions, published in the journal Natural communicationssuggest that the factors at play are not limited to any one of these factors.

“Our results suggest that initially, differences in shared family environment influenced who became infected with COVID-19 more than genetic differences,” said Katie LaRow Brown, MA, first author of the study and chair of a doctorate. candidate at Columbia University who collaborated with Cedars-Sinai on this study.

“Over time, however, the importance of these differences in the shared home environment diminished – and the importance of genetics increased – eventually eclipsing the shared home environment.”

COVID-19 has infected more than 340 million people in the United States, highlighting the urgency of conducting therapeutic research and discovering potential treatments. However, until this study, little was known about how an individual’s environment and genetic background impact their experience with the virus.

Using electronic health records from New York-Presbyterian/Columbia University Irving Medical Center, investigators identified 12,764 patients who received conclusive results – positive or negative – from a PCR test for COVID-19. These patients belonged to 5,676 families with an average of 2.5 family members who had a COVID-19 attack. The period studied was from February 21, 2020 to October 24, 2021.

The investigators’ analysis found that early in the pandemic, genetics accounted for 33% of the variation in susceptibility. However, in the second half of the study, genetics accounted for 70% of the variation in susceptibility.

In measuring the severity of COVID-19 in patients, investigators also found that a patient’s genetics were more of a factor than their home environment. Severity of illness was defined by length of hospital stay. Genetics explains 41% of the variation, while shared environment explains 33%.

“We were particularly surprised by the susceptibility percentages,” said study senior and corresponding author Nicholas Tatonetti, Ph.D., vice chair of operations in the Department of Computational Biomedicine and associate director of Computational Oncology. at Cedars-Sinai. Cancer. “Since it is an infectious disease, we assumed that differences in home environment would explain most of the variation for the entire study.”

Although Tatonetti says his team of investigators can’t be sure, they suspect that over time the gaps between people’s home environments have changed in important ways.

“This work also suggests that specific genetic factors influencing susceptibility and severity have not been fully identified,” Tatonetti said. “This is very important in terms of directing resources and defining future research goals.”

Jason Moore, Ph.D., chair of the Department of Computational Biomedicine and professor of medicine, said the study provides critical information and analysis for future pandemics.

“The age-old debate over what matters more – genetics or your environment – ​​continues through the work of this important study,” Moore said.