Can Nurturing Environments “Turn On” Protective Genes?
Yes, indeed, through a process called epigenetics. Chances are you’ve never heard of changes in gene expression, since most people were taught your genes are for life. Well, we do have our genes for life—but many of our genes change their expression based on our social interactions at home, at school or in the community. Many of the genes that change the most involve our brains.
What many people don’t know is that some genes, like the 16 gene variations of BDNF, “listen” to the social and biological environment. If the gene variation “hears”, for example, lots of threats coming from other humans or risk to future, the gene may express itself differently. If the gene “hears” reinforcement, and support from other humans, it may express itself differently—preferentially calculating a longer life.
These expressions have been selected by evolution, and have reproductive advantage in different circumstances. Remember, since the invention of stone tools, humans became the worst predator of other humans, and other humans became the major source of safety. That is a unique evolutionary paradox of humans.
Now some readers who know a bit about my professional work may know that an early protective strategy in primary grades, the PAX Good Behavior Game (http://bit.ly/NREPP) has powerful protective effects on children’s futures 10-20 years later. For example, one or two years of exposure to PAX Good Behavior Game could have these long-term benefits for each cohort of nearly 4 million first graders each year in America, based on the prior studies and the predictions inferred:
Here are the estimates based on previous research findings:
• 350,306 fewer young people will need any form of special education services
• 226,668 more boys will likely graduate from high school
• 272,002 more boys will likely attend college
• 361,444 more girls will likely graduate from high school
• 282,440 more girls will likely attend college
• 39,564 fewer young people will commit and be convicted of serious violent crimes
• 391,518 fewer young people will develop serious drug addictions
• 267,881 fewer young people will become regular smokers
• 144,244 fewer young people will develop serious alcohol addictions
• 197,510 fewer young women will contemplate suicide
• 267,881 fewer young men will attempt suicide
These are extraordinary changes from a simple program that teaches self-regulation to children, reduces exposure to peer aggression, rewards peer cooperation, and helps children experience a more positive daily life everyday in school. All of this happens as a daily routine, not as a curriculum or series of lessons.
With all these long-term behavior changes, my colleagues and I at Johns Hopkins (where we are involved in ongoing studies of the PAX Good Behavior Game) have long thought that changes MUST be happening in the expression of genes like those found in BDNF. It turns out to be true.
A bright young scientist at Hopkins lead such a study to measure such changes, using fancy tools by comparing children who were randomly assigned to control condition first-grade classrooms, to first-grade classrooms with what is now the PAX Good Behavior Game, or to first-grade classrooms where every parent could access parenting supports. Dr. Rashelle Musci and others extracted single-nucleotide polymorphisms (SNPs) from the BDNF gene samples from all three groups of children, just after they graduated from high school. About 14 years after the young people had experienced the experimental conditions.
While the preventive interventions tested in the classrooms or among the families were not rocket science, the gene analyses are. You can read more about the technical details from the study , which I am happy to share. What happened? Well about half of the children had particular group of variants of BDNF genes, associated with disposition toward aggression and impulsivity. These are the same gene clusters that predict longer-term problems of mental, emotional, and behavioral disorders. That group of genetically “at-risk” children were most profoundly affected by the PAX Good Behavior Game and secondarily by the parenting supports offered to the families.
From all this, we now infer that the BDNF gene expression was changed by the environment. Recently, new methods can allow us to see the traces of how the gene expression was changed, because there detectable markers on the genes to reveal the traces of the changes. In our newer studies in Manitoba and the US, we plan to set in motion instrumentation to measure these changes. What is remarkable is that a nurturing environment, vis à vis a medication, made this difference. What is further remarkable is that either nurturing environment left a permanent change on both behavioral traits, which medications do not.
To explain the study visually, I have created an illustration that you can review, which you can download here: http://bit.ly/BDNFPAX (Note: one has to click “download” for the PDF when the screen comes up, which takes a few moments.)
1. Musci RJ, Bradshaw CP, Maher B, Uhl GR, Kellam SG, Ialongo NS: Reducing aggression and impulsivity through school-based prevention programs: A gene by intervention interaction. Prevention Science 2013:No Pagination Specified.