First impressions not only count—they are surprisingly accurate, at least when it comes to detecting whether a stranger is “made” to be compassionate, trustworthy or kind. New research by the University of California, Berkeley suggests that it can take just 20 seconds to recognize who is genetically so inclined. Two dozen couples participated in the study and provided DNA samples. Researchers documented them as they talked about times when they had suffered. A separate group of observers that did not know the couples were shown 20-second video segments of only the listeners and asked to rate which participants seemed most compassionate, based on facial expressions and body language. The listeners that received the highest ratings for empathy turned out to possess a particular variation of the oxytocin receptor gene known as the GG genotype. Dubbed the “love hormone”, oxytocin is naturally secreted into the bloodstream and the brain, where it promotes social interaction, bonding and romantic love. “People can’t see genes, so there has to be something going on that is signaling these genetic differences to the strangers,” says Aleksandr Kogan, lead author of the study. “What we found is that the people that had two copies of the G version displayed more trustworthy behaviors: more head nods, eye contact, smiling and open body posture. These behaviors signaled kindness to the strangers.”