A human’s genetic material, the DNA and RNA, primarily lives inside our cells. However, there are always tons and tons of dying cells as well, so what happens to that genetic material?
That is “cell free” DNA and RNA. It essentially floats around in our blood upon being released by dying cells. This cell free DNA and RNA is extremely useful because scientists can access it via blood tests and study it in a variety of different ways. One such use case is early detection of having a premature baby.