Scientists have determined that first responders to the World Trade Center during the September 11, 2001, terrorist attacks have increased levels of mutations that may escalate their risk for blood cancers or cardiovascular disease, according to a study published by Jasra et al in Nature Medicine.
The researchers determined that a significantly higher percentage of World Trade Center first responders have an increased mutational burden when compared to blood sample data from BioVU, Vanderbilt University’s biorepository of DNA extracted from discarded blood collected during routine clinical testing. Among World Trade Center firefighters, 10% had evidence of clonal hematopoiesis, compared to 6.7% for firefighters who were not exposed to particulate matter from the burning skyscrapers. Clonal hematopoiesis is an age-associated phenomenon marked by mutations in commonly mutated genes within blood cells that provide those cells a competitive advantage and increases risk of blood cancer and cardiovascular disease.
Study Methodology
The team accessed information about the DNA of 203 Nashville firefighters from BioVU, and then was able to use the de-identified, annotated data within the Synthetic Derivative to locate over 200 firefighters who were age-, sex- and smoking status–matched to first responders at the World Trade Center disaster. Combined with 52 firefighters recruited at the annual convention of the International Association of Firefighters, this control group was compared to those exposed to particulate matter at the World Trade Center disaster.
They also exposed mice to World Trade Center particulate matter thought to be equivalent to what the first responders absorbed. The scientists observed a significant expansion of hematopoietic stem cells 30 days after exposure.
The researchers concluded that first responders to the World Trade Center have an increased mutational burden that puts them at greater risk for blood cancers beyond what normally occurs with aging, and further studies of the particulate matter and the mechanism of blood cancer development are underway.
Disclosure: The research work was supported by the National Institutes of Health, The Leukemia Lymphoma Society, EvansMDS (an initiative of the Edward P. Evans Foundation), the V Foundation for Cancer Research, the Adventure Alle Fund, The Biff Ruttenberg Foundation, the Beverly and George Rawlings Directorship, and a gift from the Dempsey and Leinbach Families. For full disclosures of the study authors, visit nature.com.
