Is Personality Inherited? This Is How Genes Influence Us

We have all heard expressions like “he has his father’s bad temper”, “he is as kind as his mother”, “his grandfather was also naughty when he was little” and many others like that.

That is why, based on the fact that it seems that our way of being is something that runs in the family, To what extent is personality inherited? What is more important when defining it: genes or the environment? How do you know? Let’s see it below.

    Genetics and behavior, what relationship do they have?

    As with most animals, human beings inherit DNA from our parents, with half of it made up of maternal DNA and the other half of paternal DNA. This genetic inheritance influences various aspects, including our behavior, character and values However, and this is the point that differentiates us from animals, is that we are capable of setting goals and having aspirations, which can be promoted by the family and cultural environment in which we live.

    Another difference that sets us apart from other animals is that humans are aware of our genetic inheritance, that is, to what extent we are so similar to our parents, both psychologically and physically, and, resorting to free will, we can try to distance ourselves from what is supposed to be found in our genes. This is the field of study of behavioral genetics.

    Although it is known that behavioral aspects, both those that are adaptive and those that imply psychopathology, are to a greater or lesser extent heritable, A mistaken belief before the development of the Human Genome Project was that each behavior or aspect of personality and intelligence would be delimited by one or a reduced group of genes However, the research found that there was no single gene for, for example, schizophrenia, giftedness or the dimension of extraversion.

    Each of these aspects, and practically all of human behavior, depends on the interaction of several genes, which can number in the thousands. Each gene has a tiny impact on personality, but together they shape it and make it similar to that of the parents.

    Genes versus environment: who will win?

    The influence of genes and environmental factors on an individual’s behavior is highly variable throughout life. It has been seen that families, who are in themselves an environmental factor, have a notable influence on the cognitive abilities of the child during their earliest childhood. Nevertheless, When these children have grown up and are old enough to go to primary school, it seems that genes take over blocking environmental influences.

    Obviously, the statement that six-year-old children are pure heredity and no environmental influence is false. Education at school, along with contact with other children and the experience of what type of events, benign or unfavorable, shape their way of being and their knowledge, however, it is in these years that their genetic code seems to be more relevant when determining your personality.

    In fact, between three and six years old, children try to find an environment that suits them well, that is, they select friends based on their way of being, They try to create an environment that is in accordance with their predispositions For example, a child with tendencies to be more active will surely feel interested in sports, which will motivate him to play soccer in the schoolyard and have contact with other children who enjoy this activity.

      Is personality inherited?

      The approach to the heritability of personality has been carried out through the best type of study that behavioral geneticists could have achieved: twin studies, both with monozygotic or genetically identical twins, and with dizygotic or fraternal twins. These experiments are ideal, especially when identical twins have been separated at birth Those traits that they share, despite having grown up in different homes, will be attributed to genetic factors.

      Although this type of research continues to have some methodological problems, there are certain patterns in the results. As the most powerful personality model today is McCrae and Costa’s Big Five, in which personality is defined based on five large dimensions: extraversion, cordiality, neuroticism, openness to experience and responsibility.

      Studies that have studied the personality of twins, both identical and fraternal, indicate that there is a high heritability of traits, especially when they are monozygotic twins. This means that If, for example, an identical twin is cordial, the other twin, with high security, is also cordial This is a clear indication that personality is greatly influenced by genetic inheritance.

        To what extent does genetics influence?

        When it is said that something is encoded in genes and is a product of heredity, mention is made of the concept of heritability of a certain trait. Heritability indicates what percentage of variation in the traits of two individuals is due to genetic causes A high percentage of heritability indicates that the variation of the trait, for example being creative, has a great role in genes, while a low heritability means that environmental factors are more important.

        Research suggests that the heritability of personality traits is around 40%-50%. This means that about half of the variation in personality can be attributed to a genetic component.

        This should not be misinterpreted, since it does not mean that half of an individual’s personality is due to genetic factors. Non-shared environmental factors would explain about 30% of the variation, and shared ones 20%.

        What should be clear about the concept of personality heritability is that it does not indicate that we have about a 50% chance of inheriting our parents’ personality, or that we will share 50% of that personality. The heritability data indicate that, for example, If one person is creative and another is less so, a good part of that difference is due to genetics and the rest is due to having received influences from the environment, both shared and non-shared.

        Heritability should not be confused with the idea of ​​genetic determination The latter refers to the fact that genes can determine a specific trait, as long as the gene or genes involved in such determination are known.

        Thus, when analyzing to what extent a certain personality trait is heritable through genes, we must keep in mind that we are not analyzing the probabilities of receiving that characteristic from paternal or maternal DNA, but rather This is a relative estimate, based on comparisons between individuals and that focuses on variation.

        Furthermore, it must be taken into account that in many respects, cultural phenomena are so ubiquitous that they can easily be confused with something determined by genetics. For example, the degree of religiosity of people: for centuries, practically everything in the world showed religiosity to a greater or lesser degree, and only in recent times has it been seen that it is a phenomenon closely linked to cultural dynamics.

        In the same way, the influence of genetics on personality is not studied from the idea that a certain way of behaving is “natural” and is present to different degrees in all people due to genetic aspects, but rather it is taken into account that Genes and experience are constantly interacting, even where it doesn’t seem like it.