We've known for decades that abused and neglected children develop anxiety, depression and addictions more often than other children, and that they're more likely than their well-cared-for peers to engage in self-destructive behaviors or attempt suicide.
Until recently, what's not been understood is whether the abuse causes biological changes leading to these tendencies, or if heritable traits predispose both the abuser and the victims to their respective behaviors. Now, researchers in Montreal report that people who were abused or neglected as children showed genetic changes that made them more biologically sensitive to stress. Abuse causes genetic alterations.
Scientists at McGill University
and the Singapore Institute for Clinical Sciences
compared the brains of 12 people who committed suicide and who suffered abuse or neglect as children to the brains of 12 people who committed suicide and had not suffered childhood abuse or neglect. The brains are preserved at Douglas Hospital in Montreal as part of the Quebec Suicide Brain Bank, which promotes suicide studies. The facts of the subjects' upbringing were determined by extensive next-of-kin interviews and investigation of medical records.
As is now widely known, when people experience stress or anxiety the "fight or flight" hormone cortisol
is secreted in large amounts. One way the human brain reduces the anxiety is to make receptors on brain cells that help clear the cortisol, inhibit the distress, and protect neurons from potentially damaging extended cortisol exposure.
The McGill and Singapore researchers discovered that the genes responsible for coding these receptors were 40% less active in people who were abused as children compared to those who were not. They also found the same differences between the abused group and the brains of 12 control subjects, who had not been abused and died from causes other than suicide.
The findings clearly indicate that abuse and/or neglect can result in changes at the genetic level, leading to increased risk of mental illness later in life.
This is one more reason to require that Child Protective Agencies focus on the wellness of a child above all else, including preservation of family units and parental rights.