'CSI' Test Can Tell Age From Drop of Blood

A new blood test from the Netherlands can determine an individual's age within a range of 9 years, the Telegraph reports. The method works by looking at a genetic feature of T cells that diminishes at a constant rate over time. The test can work with a very small amount of blood, including "situations where only bloodstains are available, which covers a large proportion of crime cases," says the lead researcher. “I wouldn't be surprised if it could be used on historical blood stains that are decades or hundreds of years old.”