Scientists have a discovered a gene that they believe allows some kids to shake off abusive or neglectful parents to become happy adults
We know that bad parents have the power to mess up a kid. Almost any self-examining adult can tell you that. But some kids seem less susceptible to the incompetencies of their parents. They're hardier. Why is it that some who grow up with neglectful or abusive parents can shake it off to emerge confident, happy adults, while others never seem to recover from their parents' shortcomings?
This phenomenon may occur because we have a genetic predisposition, not necessarily to turn in to good or bad or happy or sad people, but to be more or less susceptible to those around us. Earlier research has put forth the differential susceptibility hypothesis (DSH), which suggests that people vary in how reactive they are to the environment, both positive and negative. And based on the results of a new study, kids, according to their genetic makeup, seem to vary in how susceptible they are to their parents' capabilities and failures.
The length of a gene (the serotonin transporter gene, 5-HTTLPR) that helps determine how much of the neurotransmitter serotonin circulates in the brain varies from person to person. Having shorter copies of the gene is linked not only to lower mood, but it is also associated with being more sensitive to one's environment, both good and bad. Author of the current study, Ben Hankin, says that "5-HTTLPR has been associated in some studies with negative temperament and risk to emotional problems, so we reasoned that 5-HTTLPR may be one gene that demonstrates susceptibility, or sensitivity to the environment, and this association could happen for better and for worse."
To test this theory, Hankin and his team measured the length of this gene in about 1,900 kids, aged 9-15. They also did a few measures to see what kinds of parents the kids had. In the first one, they asked the parents questions about their parenting techniques -- whether they tended to use positive, supporting methods or not. In the second, the researchers observed the parents themselves. And in the last, they asked the kids about their parents' techniques. They also measured the kids' disposition, determining whether their affect (mood) was more positive or negative.
In all of the experiments, the researchers found that kids with shorter versions of the gene were more reactive to their parents' methods, whether good or bad, than kids with longer versions of the gene. For instance, children with shorter 5-HTTLPR genes were less happy when they had unsupportive parents, but were also much happier when their parents were more supportive. In contrast, the moods of kids with longer versions of the gene were relatively stable across different kinds of parental support.
The study is interesting in a number of ways. Much more than a confirmation that parenting can overcome "bad" genes, the results suggest that some kids are a lot more reactive to their environments than other kids, and can be affected more than would be expected by different styles of parenting. "Our results suggest that providing such positive parenting may be especially important for these children with difficult temperaments, as such individuals appear to be more reactive and sensitive to their environment, for better and for worse," Hankin said. Fortunately, the connection works both ways, so deliberately changing parenting techniques could have a better-than-expected effect on a reactive child.
Previous literature has found other ways in which the 5-HTTLPR gene influences one's sensitivity to his or her surroundings. Hankin says that it has been linked to differences in "brain activity to negative emotional pictures, reaction time to attend to emotional faces, and cortisol release (a stress hormone) in response to lab stressors. In each case, carriers of the short version of 5-HTTLPR showed greater sensitivity to the environment, as measured differently in each of these studies." In other words, it's not just parents that people with short 5-HTTLPR genes are reactive to -- it's a variety of environmental stimuli.
The results of the current study lead to some interesting questions: Why is there an inherent, or at least genetic, connection between being more sensitive to one's environment (both good and bad) and having lower mood? Does being extra sensitive to surroundings lend itself to negativity, is it the other way around, or is it a complicated back-and-forth?
The answer to these questions is unclear, but Hankin says that individuals with short 5-HTTLPR genes may have a harder time shaking their low mood in general. He suggests that "one possibility is that, among individuals who carry the short allele of 5-HTTLPR, they may be more prone to depression when exposed to negative, stressful environments. This could happen because they have more difficulty up-regulating positive emotions, which may lead to anhedonia, a major symptom of depression."
Why these same individuals are capable of being "extra happy" in a positive environment is still unknown. Future research will likely bring answers to the remaining questions. In the meantime, if your kids seem particularly reactive to their surroundings, make an extra effort to foster their positive side. And if you suspect that you carry a short version of this tricky gene yourself, try surrounding yourself with positive people. It may have a bigger effect than you expect.