Have you ever spotted someone in a crowd that you thought was a friend, only to discover it was simply someone who looks remarkably similar? Many of us have seen so-called doppelgängers of loved ones, family members and even ourselves. Now, a study has revealed that these doppelgängers don't just look alike – they also likely have very similar DNA, and even share personality traits. Researchers from the Josep Carreras Leukaemia Research Institute in Barcelona have revealed that strong facial similarity is associated with shared genetic variants. 'These results will have future implications in forensic medicine - reconstructing the criminal's face from DNA - and in genetic diagnosis - the photo of the patient's face will already give you clues as to which genome he or she has,' said Dr Manel Esteller, senior author of the study.

From Amy Adams and Isla Fisher to Liam Neeson and Ralph Fiennes, many celebrities are regularly mistaken for one another, despite being unrelated. Now, a study has revealed that these famous faces don't just look alike – they also likely have very similar DNA. Researchers from the Josep Carreras Leukaemia Research Institute in Barcelona have revealed that strong facial similarity is associated with shared genetic variants. 'These results will have future implications in forensic medicine - reconstructing the criminal's face from DNA - and in genetic diagnosis - the photo of the patient's face will already give you clues as to which genome he or she has,' said Dr Manel Esteller, senior author of the study. In 2015, researchers revealed that the chance of finding your doppelganger is one in a trillion. Teghan Lucas, a student at the University of Adelaide, conducted the study using a large database of face and body measurements from almost 4,000 individuals, combined with mathematical equations.