Wednesday, December 27, 2017

Family Dysfunction and Gene Expression: Effects on Personality and Behavior

Jenny Macfie, Ph.D., Department of Psychology, University of Tennessee Knoxville

It’s amazing what you can discover if you actually look

When it comes to the “scientific” literature about what causes borderline personality disorder (BPD) and other forms of self-destructive and self-defeating behavior, readers of my blogs know that I think genetic influences are way overemphasized and the effects of dysfunctional family dynamics and child abuse ignored as much as possible.

In my clinical practice, I see dramatic evidence that the effects of the family dysfunction on behavior are often passed down from one generation to the next.  A few studies have also looked at this, and in every case supported this viewpoint.

Two more recent studies support my views in general about what creates the disorder.

Jenny Macfie and others, following the work of Karlen Lyons-Ruth described in a previous post, actually watched the interactions between children aged 4-7 and their mothers with BPD (“A Mother’s Borderline Personality Disorder and Her Sensitivity, Autonomy Support, Hostility, Fearful/disoriented Behavior, and Role Reversal with her Young Child,” Journal of Personality Disorders 31(6):  pp. 721-737, 2017).  

The pairs were given a task with the following instructions: “This puzzle is for your child to complete, but feel free to give any help your child might need.” A researcher presented one puzzle at a time in order of increasing difficulty.  Mothers who did not have the disorder and their child were also given the task. All interactions were observed and scored.

Mothers who had BPD “demonstrated significantly less sensitivity and autonomy support [supporting the child’s efforts to solve the puzzles without the assistance of the parent], more hostility, more role reversal, and more fearful/disoriented behavior in interactions with their children than did comparison mothers.

“Role reversal” is the child taking care of the mother instead of the other way around. In this study they specifically looked at mothers deferring to their child’s demands, the pair acting like playmates (for example, child abandons task and the two run around the room rather than the mother setting limits), and mothers taking the child’s attention away from the task by demanding signs of affection from the child.

There was no group of mothers with other personality disorders so we do not know if the researchers results are specific to mothers with BPD.

In a second, unrelated study, Pierre Eric-Lutz and his colleagues looked at the effects of child abuse on the expression of genes that control the development of the brain (“Association of a History of Child Abuse with Impaired Myelination in the Anterior Cingulate Cortex: Convergent Epigenetic, Transcriptional, and Morphological Evidence,” American Journal of Psychiatry 174 (12), pp.1185-1194, 2017).

Epigenetics refers to the process by which environmental influences turn genes on and off. Most genes in a cell are not operating at all at any given time. Epigenetics ties environmental and genetic influences together in ways that a lot of people in the various mental health field either seem to be unaware of, or consciously ignore. The anterior cingulate cortex is a part of the brain heavily involved in making decisions regarding what to do in various social situations.

Without going into the authors’ methodology, which was quite sophisticated, the study found that individuals abused during childhood showed significantly decreased expression of a large collection of genes involved in myelination of cells in that part of the brain. Myelination is process which markedly changes the level of functioning of brain cells that are part of so-called white matter.

Once again, we find that one of the main purposes of the genes that create the brain in human beings is to make humans exquisitely sensitive to the social environment.


  1. But there is no therapy that can myelinate those neurons, so therapy turns into bailing water for those afflicted with the suite of personality disorders handed to them by their parents.

    1. Actually new connections and neural pathways form throughout life, so it's not as hopeless as that.