The time old question is ‘are your personality traits based on nature or nurture?’ Does your inherited genetic material determine your personality or is it the environment you grew up in or could it be a mixture of both? The Minnesota study of Twins conducted between 1979 and 1999 viewed pairs of identical twins, whose genetics are at least 50 percent interchangeable, and fraternal twins, whose are about 20 percent interchangeable. Some sets of twins studied grew up in the same household and others grew up apart from each other, in different environments. The study concluded that identical twins had similar personalities, regardless if they grew up together or apart. This outcome is looking more towards the fact of genetics determining personality traits. And while the twin study strongly suggests that personality traits are dependent on inheritance, environmental factors could still play a role in personality. Think of the Theory of evolution. The idea of survival of the fittest would indicate that environmental factors would influence your personality.
I believe that both genetic inheritance and environmental factors influence our personalities. Our personality traits are a mixture of both nature and nurture. The twin studies have strong evidence supporting the idea that genetics determines your personality traits but I think the way a person was brought up affects them as well. For example, people who grew up in the city and people who grew up in more of a country setting have different personalities, which would mean their environment influences them. What do you think?