Mount Sinai Researchers: Why COVID-19 May Be Less Common in Children Than Adults
Findings Published in JAMA Could Lead to Potential Biomarker of Susceptibility
The virus that causes COVID-19 uses a receptor known as ACE2, found on the surface of certain cells in the human body, to enter its victims. Now, Mount Sinai researchers have found that children have lower levels of ACE2 gene expression than adults, which may explain children’s lower risk of COVID-19 infection and mortality. Gene expression is a measure of how much a gene is transcribed. These results, published in JAMA on Wednesday, May 20, may point to a potential biomarker of susceptibility to the virus, known as SARS-CoV-2.
“ACE2 expression may be linked to our susceptibility to COVID-19,” says lead author Supinda Bunyavanich, MD, MPH, Professor of Genetics and Genomic Sciences and Pediatrics, Icahn School of Medicine at Mount Sinai. “ACE2, which stands for angiotensin converting enzyme 2, is a receptor that some might be familiar with because of its role in blood pressure regulation. The coronavirus uses ACE2 to enter the human body, where it spreads. ACE2 is known to be present in our airway, kidneys, heart, and gut. In our study, we took this knowledge a step further, finding that there are low levels of ACE2 expression in the nasal passages of younger children, and this ACE2 level increases with age into adulthood. This might explain why children have been largely spared in the pandemic.”
The research focused on ACE2 due to its significance in COVID-19 infection. The nasal passages are usually the first point of contact for SARS-CoV-2 and the human body. Dr. Bunyavanich’s study is one of only a few examining the relationship between ACE2 in the airway and age.
The retrospective analysis, led by Dr. Bunyavanich, examined nasal passages epithelium from Mount Sinai Health System patients aged 4 to 60. The researchers found ACE2 gene expression in nasal epithelium was age-dependent, lowest in younger children and increasing with age into adulthood.
About the Mount Sinai Health System
The Mount Sinai Health System is New York City's largest academic medical system, encompassing eight hospitals, a leading medical school, and a vast network of ambulatory practices throughout the greater New York region. Mount Sinai advances medicine and health through unrivaled education and translational research and discovery to deliver care that is the safest, highest-quality, most accessible and equitable, and the best value of any health system in the nation. The Health System includes approximately 7,300 primary and specialty care physicians; 13 joint-venture ambulatory surgery centers; more than 415 ambulatory practices throughout the five boroughs of New York City, Westchester, Long Island, and Florida; and more than 30 affiliated community health centers. The Mount Sinai Hospital is ranked on U.S. News & World Report's "Honor Roll" of the top 20 U.S. hospitals and is top in the nation by specialty: No. 1 in Geriatrics and top 20 in Cardiology/Heart Surgery, Diabetes/Endocrinology, Gastroenterology/GI Surgery, Neurology/Neurosurgery, Orthopedics, Pulmonology/Lung Surgery, Rehabilitation, and Urology. New York Eye and Ear Infirmary of Mount Sinai is ranked No. 12 in Ophthalmology. Mount Sinai Kravis Children's Hospital is ranked in U.S. News & World Report’s “Best Children’s Hospitals” among the country’s best in four out of 10 pediatric specialties. The Icahn School of Medicine is one of three medical schools that have earned distinction by multiple indicators: ranked in the top 20 by U.S. News & World Report's "Best Medical Schools," aligned with a U.S. News & World Report "Honor Roll" Hospital, and No. 14 in the nation for National Institutes of Health funding. Newsweek’s “The World’s Best Smart Hospitals” ranks The Mount Sinai Hospital as No. 1 in New York and in the top five globally, and Mount Sinai Morningside in the top 20 globally.