“We’re taking a really different approach. We leverage epigenomic profiles, which contain information about which tissue the cell-free DNA is derived from and if it’s cancerous,” Curtis said. “And while certain mutations are important hallmarks of cancer, there’s a unique profile that the epigenome provides, including clues about the cell’s activity or state.”
It’s a lot to ask of a run-of-the-mill blood draw, but Curtis and her group are devising a search tactic that goes beyond identifying rare mutations in DNA. She’s looking at epigenomic footprints, a type of marker typically embedded in DNA. While these markers are often found enclosed in the cell, Curtis takes advantage of cell-free DNA, which floats openly in the bloodstream after shedding from a tumor or from healthy tissues.