Every trait is influenced by both genetics and the environment in which the child grows up. Someone may be born with a tendency to be more outgoing or curious, but if an event in their childhood stymies these traits than the end result could be an adult who is withdrawn from others and rarely asks questions. Essentially, a child is born with a predisposition towards certain behavioral characteristics, however, events that occur throughout their life can modify their behavior and thus their personality. The degree to which these events change how a person acts is partially determined by the individual’s differential susceptibility, or how sensitive a person is to positive and negative experiences. A person’s degree of differential susceptibility is largely determined by genetics (Berger). Although environmental factors still play a role, there are certain traits that genetics tend to have a large effect on. A recent study performed by Chi-Hua Chen found that there was a correlation between certain personality traits, such as neuroticism and extraversion, and specific genes. He and his team also found a connection between behavioral characteristics and the likelihood of developing a psychiatric disorder. For example, individuals that expressed the genes WSCD2 and PCDH15 were more likely to be extroverted, but they also tended to be diagnosed with ADHD (Nield). This study doesn’t prove that simply because someone is born with a certain gene they will automatically display a specific behavioral trait. Instead, it shows that some people are predisposed to developing certain personalities and, unfortunately, psychiatric disorders. More research needs to be done to determine to what degree each of these genes influences the development of behavioral characteristics in an individual. Along with the behavioral traits that seem to be heavily influenced by a person’s genetics, there are also segments of our personalities that come mainly from environmental influences. Studies of identical twins reared either together or separate have often been used to study the effects that the environment has on personality development. In one particular study, researchers found that twins who were raised apart from each other often showed differences in their levels of agreeableness. This finding suggests that this specific personality trait is influenced primarily by environmental factors that a child experiences as they are growing and maturing (Bergeman et al.). Another trait that is largely impacted by the environment is an individual’s openness to new and different experiences. People who are exposed to stress early in their development tend to be more open to trying new things, while those who experience little early stress aren’t as open to change (Torgersen and Janson). Even though some traits appear to be primarily influenced by genetics while others have more to do with environmental factors, it is important to remember that each aspect of our personality is influenced by both. An individual’s behavior results from a mixture of their genetic code and the experiences they have had, each force constantly being impacted by the other.