Human blood contains tiny shards of DNA, released as cells die. Cell-free DNA (cfDNA) tests examine these shards. If an analysis can determine where the DNA shards came from, it would be possible to detect damage in different parts of the body. cfDNA tests require only a simple blood draw and could one day be used to diagnose a wide range of illnesses, including diabetes, at their earliest stages, when they are often easier to treat. Read more