DNA At the Fringes: Twins, Chimerism, and Synthetic DNA

Plenty of things can go wrong in DNA testing in a run-of-the-mill case. Problems with interpreting the sample, determining the right match probabilities, and ensuring the integrity of the sample and the evidence collection and testing process are everyday, ordinary kinds of issues that may arise. But, of course, sometimes the extraordinary occurs.

Forensic DNA testing is to some extent a field of frontiers. Researchers continue to probe how our DNA works, filling the pages of science journals with their new discoveries. Technologists constantly refine the instruments used to conduct DNA testing, enhancing speed and sensitivity. Forensic DNA testing takes advantages of some of these advances as they occur, but it does not have frictionless adaptability. For instance, the government has built an enormous DNA database around a specific kind of DNA test, and sunken costs prevent laboratories from instantly converting to the latest in testing instrumentation.

But cutting-edge science still crops up in the criminal justice system, typically inspired by the exigencies of an individual case. One such example livening up the otherwise predictable environs of an...