Kindness might be a genetic trait. It appears to be connected to a person's oxytocin receptor genes — people who had a GG genotype were found to be generally more trustworthy, empathetic and "pro-social" than people who had other genotypes in a study published in Proceedings of the National Academy of Sciences. What's more, this trait is apparent to strangers even through brief contact. In the study, researchers identified the genotypes of couples, then had one partner listen while the other told a story that involved suffering while they videotaped the couple. They then had other people watch the tapes, and the observers picked out nine of the 10 non-GG genotype people in about 20 seconds.
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