Is Borderline Personality Disorder Genetic or Created by One’s Environment or Both?

In a few words, YES, I believe it is genetic and subject to exacerbating environmental factors. My psychiatrist believes my mother has it (and she definitely acts like she does). Further, the erratic behavior of her father (my biological grandfather) suggests strong genetic ties. The good news is that not every child of a borderline parent ends up developing BPD. I have three younger brothers who seem to be BPD-free, although two of them have needed to visit psychologists on occasion for help with depression and Attention Deficit Disorder. Medication was prescribed in both instances.

My greatest fear in life would be passing on bad genes to my offspring. My debilitating combination of Type 1 Juvenile Diabetes (also thought to have genetic underpinnings) and BPD makes me think twice about wanting to reproduce. No, I’m not overestimating my importance to the human race ( 🙂 ), I just believe that having children is life’s biggest decision and it should not be taken lightly. To the greatest extent possible, people should reproduce responsibly.

An article titled “Genetic Causes of Borderline Personality Disorder ” confirms anecdotal evidence I’ve read online and heard from others:

“Studies of BPD in families show that first degree relatives (siblings, children, parents) of people treated for BPD are 10 times more likely to have been treated for BPD themselves than the relatives of people with schizophrenia or bipolar disorder. However, while this suggests that BPD runs in families, studies of these type do not tell us exactly how much of BPD is due to genetics. First-degree relatives often also share environments, for example, siblings may be raised together by the same parents. So, these studies may be reflecting, in part, environmental causes of BPD.”

This conclusion might represent some recent progress in the study of genetic factors and BPD. A 2000 National Institutes of Health article takes a much more ambivalent stance, suggesting a high – yet to be proven – correlation existing between genes and the development of BPD. The following quote is from the article abstract, “Genetics of patients with borderline personality disorder “:

“An overview of the existing literature suggests that traits similar to BPD are influenced by genes. It is too early to say to what extent BPD is also influenced by genes, but because personality traits generally show a strong genetic influence, this should also be true for BPD. Nonetheless, if the equal-environment assumption were to be violated for MZ and DZ pairs, twin studies may be overestimating genetic effects and hiding the effect of common family environment. The less than-ideal reliability of measurements used in this research may also reduce the effects of genes and common environment while increasing the effects of unique or nonshared environment. The effect of genes on the development of BPD is likely substantial. The effect of common family environment may be close to zero. More studies, large and small, are needed to reach firmer conclusions about the influence of genetics on BPD.”

Essentially, both authors seem to conclude that further research is required. This begs the salient question, “Is there any good research being done exploring BPD and genetics?”

As late as 2009, a group in the Netherlands did indeed complete research on genes and the development of BPD. In the discussion of their findings, they suggested that individuals genetically predisposed to BPD were more likely to develop it in an unfavorable environment, opposed to individuals who were not as genetically “sensitive”. This is an obvious but important conclusion:

“The interaction, however, between the influences of genes and environment on the development of BPD has not been studied. Gene by environment interaction implies that genes determine the degree to which an individual is sensitive to an environment. In the presence of gene-environment interaction, individuals with a ‘sensitive’ genotype will be at greater risk of developing BPD if an undesirable environment is present, than individuals with an ‘insensitive’ genotype. In the present study, gene-environment interaction would be included as part the unique environmental variance. Future research should focus on possible sources of unique environmental effects and gene-environment interaction to develop a comprehensive model of the development of BPD.”

Source: “Familial Resemblance of Borderline Personality Disorder Features: Genetic or Cultural Transmission?

Overall, one definite conclusion can be reached: studying BPD and the genes of those who have it is difficult in settings where twins are not present, as is the case in nearly all instances of BPD. I myself am not a twin but a first degree relative (mother-son relationship) of someone who certainly also has BPD. My other siblings DID NOT develop a BPD diagnosis, which could be attributed to two reasons: they are not as genetically “sensitive” as I am, and/or the environment of their upbringing was different than mine.

The second conclusion of my own discussion of BPD problems raises in interesting question: could evolving parenting styles used with subsequent children lessen the degree to which they might get a BPD diagnosis? Based on my own life experiences, I wholeheartedly say YES!

Think about it: if your mother or father has BPD but eventually raises your siblings differenly than you who does have BPD, parenting styles, ie. upbringing and environment, clearly matter. My parents did not raise me properly, and since my genetic predisposition to BPD was already present, I was essentially “ripe for the picking”.

Ultimately, my parents – comprised of one BPD mother – adapted their parenting methods by chance or because they realized they screwed up with the first one; ie. me, who was eventually diagnosed with BPD. Either that, or their style DID NOT evolve and my other brothers simply didn’t have the genes to react successfully with their problematic parenting to eventually create a BPD diagnosis of their own.

Although I lack the clinical credentials to reach a scientific conclusion about the unfortunate path towards living with BPD, I am willing to venture a guess that genes do matter as much as environment.

If anyone wishes to examine me for the purposes of scientific research, I am happy to comply, but will the rest of my family? Doubtful! 🙂