Are you the "nice guy" in your social circle? It might be in your genes. People with certain versions of two genes are able to overcome their fears about the world in order to help others. These genes—which contain instructions for hormone receptors—show that social behaviors depend upon more than just education. The hormones involved—oxytocin and vasopressin—have been previously associated with “niceness” in other research studies. People exposed to oxytocin in the lab are more social. This hormone has also been called the “love drug” or “cuddle chemical” because of its effects on relationships. Hormones act in the body by attaching to appropriate receptors. Slight differences in a gene’s sequence can affect the structure of those receptors, and alter how the hormones bind to them. In the current study, researchers surveyed people about their social attitudes toward the world, other people, and civic duties like donating blood and reporting crimes. They also collected DNA samples from 771 people to see what versions of the hormone receptor genes they carried. The researchers found that people who thought the world was threatening were less likely to help others, unless they had specific versions of the two genes. In that case, the variation in the receptors enabled people to overcome their negative social attitudes. Genetics, though, only made “a contribution in the presence of certain feelings people have about the world around them.” Researchers say they haven’t discovered the “niceness” gene, just one piece of the puzzle. Next time your neighborhood needs volunteers for a block party, think about how your genes might affect your answer.