TUESDAY, Oct. 4 (HealthDay News) -- As scientists continue to tease out the impact of nature versus nurture, it appears that kids unlucky enough to get a "downer" personality gene can end up with sunnier outlooks when they're parented in a warm, positive manner.
A new study on nearly 1,900 children aged 9 through 15 with a gene variation predisposing them to lower serotonin levels in the brain -- which can lead to a gloomier disposition -- suggests the youths were more likely to maintain happier emotions when exposed to positive parenting. So-called "genetically susceptible" children who experienced unsupportive parenting showed fewer positive emotions in the three independent experiments comprising the study.
Study author Benjamin L. Hankin, an associate professor of clinical child and developmental cognitive neuroscience psychology at the University of Denver, used a horticultural analogy of weeds versus orchids to describe how genes and upbringing combine to affect children's outcomes.
"A weed will grow anywhere," Hankin said, "but if you're an orchid, you're probably more reactive and responsive to your environment. If you have a really negative, punishing environment, you're probably not going to grow up to be a beautiful orchid."
The study is published online Oct. 4 in the journal Translational Psychiatry.
In the first experiment, parents reported on the degree to which they used positive or supportive parenting techniques; in the second, their behaviors were observed in a laboratory. In the final experiment, the children reported their own perceptions of warm, positive parenting.
Participants all carried a shortened version of the 5-HTTLPR gene, which Hankin noted has been linked in prior research to anxiety and depression. In this case, researchers viewed the gene as leading toward a more sensitive, reactive disposition, and the findings were the first empirical evidence that genetically susceptible individuals would suffer because of negative environments and flourish in positive ones.
"What was most surprising was we found the same result in three independent studies," Hankin said. "There's a lot of controversy around these kinds of genetic studies because a lot of time the results don't replicate. As scientists, when something happens three times in a row, we start to believe it."
Marta Flaum, a child psychologist in Chappaqua, N.Y., said the study highlights the importance of environment in determining whether children will become happier and more successful adults.
"As science becomes more sophisticated, we're better able to identify these genetic or biologic markers and can predict what's going to happen in kids," she said. "We know how important early intervention is, and this study points in a direction to help us intervene."
Hankin noted that most people have no idea whether their genes predispose their children toward lower brain serotonin levels, but children who seem chronically moody are likely to be affected.
"So if you're a parent, and you have a kid who has a difficult temperament, your parenting matters a lot," he said. "Being a positive parent can accomplish a lot."
But regardless of genetics, every child can benefit from warm, supportive parenting, said Rahil Briggs, a child psychologist and director of the Healthy Steps Program at Montefiore Medical Center in New York City.
"Parenting is an incredibly powerful tool for change in children, so supportive parenting is the way we want to go for any kid," Briggs said. "That holds true for all kids, even children who come into this world with little handicap in genetics and susceptibility."
The Nemours Foundation has more information about positive parenting.
SOURCES: Benjamin L. Hankin, Ph.D., associate professor, clinical child and developmental cognitive neuroscience psychology, University of Denver; Marta Flaum, Ph.D., child psychologist, Chappaqua, N.Y.; Rahil Briggs, Psy.D., child psychologist, director, Healthy Steps Program, Montefiore Medical Center, New York City; Oct. 4, 2011, Translational Psychiatry, online
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