Using a panel of 24 SNPs, Polish researchers are able to predict the hair and eye color of an individual from whom a forensic or ancient sample originates, as they report in Investigative Genetics. They assessed the panel, called the HIrisPlex assay, on DNA from both contemporary bone samples and older, World War II-era and medieval tooth samples. Of those 26 samples, the researchers were able to analyze 24.
One of those was a sample from General Władysław Sikorski, the commander-in-chief of the Polish Armed Forces and the prime minister of the exiled Polish government who died in a plane crash in 1943. The researchers' analysis shows that Sikorski likely had blond hair and blue eyes, as portraits painted after his death and some written documents also indicate.
Another sample was from a woman found buried at an abbey, about 800 years ago. According to the researchers, she likely had dark blond/brown hair and brown eyes.
While the panel may help researchers determine what ancient humans may have looked like, author Wojciech Branicki from Jagiellonian University in Kraków, Poland, says that it also has forensic applications, as LiveScience reports. "Some of our samples were from unknown inmates of a World War II prison," Branicki says. "In these cases, HIrisPlex helped to put physical features to the other DNA evidence." He also notes that there are likely more markers that he and his colleagues can include in their test.