Psychologists have long thought that environment plays a crucial role in shaping personality, but a new study of 837 pairs of U.S. twins shows that genetics strongly influences several personality traits.
Identical twins are used in these types of studies because they have the same DNA, and often share the same home environment. By comparing them to non-identical twins—who don’t share the same DNA—scientists can differentiate between the influence of genes and upbringing.
In this study, published in the Journal of Personality, researchers measured psychological well-being using questions like: "Are you influenced by people with strong opinions?" and "Are you disappointed about your achievements in life?"
Genes had the strongest influence on self-control, the ability of people to show restraint and persistence when faced with obstacles or challenges in life. Learning, social skills and having a sense of purpose were also affected by genetics, although to a lesser degree.
Genetics played a more important role in shaping the personalities of the twins in the study than did either home environment or surroundings.
It’s difficult to escape the genes that you inherit from your parents, but traits like self-control can help you make the most of what you are born with.