If a parent suffers from borderline, it does not automatically mean that you suffer from the disorder itself. So far, no direct inheritance has been proven. Even a certain borderline gene does not exist.
Twin Studies: The Importance of the Heritage
Nevertheless, genetic components are suspected that may increase the propensity for the disease. This is the result of family, adoption and above all twin studies. Thus identical monozygotic twins could have a much higher concordance (Latin for "condordare") compared to dizygotic ones. This means the following:
Identical twins are completely identical in their genetic makeup, while dizygotic twins are genetically similar in nature only to "normal" siblings. Now, if a particular trait (e.g., marked impulsivity or emotional instability) is more common in identical twins, that is, in both children than in dizygans, this is an indication of a hereditary component. Because then one can assume that the identical twins are therefore both affected, because they have received the same genetic make-up, in a sense, the borderline disease stuck.
Genetic or social heritage?
However, such features are difficult to separate from a "social heritage". Emotional instability, dealing with stressful situations and stress or the type of reactions and behaviors can also be learned.
Time and again experiences of violence formulate certain reaction patterns that are necessary to deal with the experience and to protect oneself. In addition, behaviors can also be influenced by the (negative or positive) example of other people, especially those with a role model function.
It is certain that the external environment has a major influence on the development of the disturbance. It should be immediately understandable that it makes a big difference whether a child grows up in a loving or in a difficult, even traumatizing environment.
Authors: Dr. med. Julia Hofmann, Eva Bauer (doctor)