Some mothers may be more prone to treating their children harshly during economic downturns like the Great Recession -- and a gene may be to blame for the effect.
Moms who had a variation in a gene called "DRD2 Taq1A genotype" were shown in a new study to be more likely to react negatively to economic changes in their environment compared to moms who didn't possess the variant.
The DRD2 Taq1A genotype has been shown to control how the body creates dopamine, a neurotransmiter that regulates behavior in the reward-based pathway in the brain.
The researchers looked at data from the Fragile Families and Child Wellbeing Study (FFS), which included almost 5,000 children born in 20 U.S. cities between 1998 and 2000. The mothers were interviewed after giving birth, and when their child was 1, 3, 5 and 9 years of age. Information on parenting behavior was gathered when the child was 3, 5 and 9 years old.
Harsh parenting was determined by the mother's score on the Conflict Tactics Scale, which included questions on five items on psychological harsh parenting -- like shouting or threatening the child -- and five more items on corporal punishment, like slapping or spanking.
Saliva DNA samples were also collected from 2,600 mothers and children when the child was nine to test for the genetic variant.
After gathering the data, the researchers took into account the economic conditions where the subjects were living, focusing on unemployment rates. They then discovered that moms who had the "sensitive" allele or variation of the DRD2 Taq1A genotype -- which they called the "T allele" -- were more abusive towards their children when the economy was bad, such as during the 2007-2009 Great Recession. Mothers without this genetic variation were no more likely to act harshly towards their children during this time.
When economic situations improved, mothers with the sensitive T allele were not as harsh compared to the other mothers.
They also discovered that high levels of unemployment among the subjects did not increase how abusive a mom was. Mothers with the T allele were more likely to be mean with their children when the economy was bad, even if they personally did not lose their job or had any personal changes because of the recession.
Instead, the overall unemployment rate of the city they lived in and their confidence in the economy played a larger role. A 10 percent increase in the overall unemployment rate was linked to a 16 percent increase in maternal harsh parenting among those with the T allele.
"It's commonly thought that economic hardship within families leads to stress, which, in turn, leads to deterioration of parenting quality," lead author Dohoon Lee, an assistant professor of sociology at New York University, said in a press release. "But these findings show that an economic downturn in the larger community can adversely affect parenting -- regardless of the conditions individual families face."
The researchers believed that for a T-allele mom, this meant that her fear that she would lose her job because of the current economic conditions weighed more on her than her actual poor economic status or hardship that she was facing.
"People can adjust to difficult circumstances once they know what to expect, whereas fear or uncertainty about the future is more difficult to deal with," co-author Sara McLanahan, a William S. Tod professor of sociology and public affairs at Princeton University in Princeton, N.J., said in a press release.
The study was published in PNAS on Aug. 5.
The researchers believed they would see this effect because of prior research. People with this T allele had been previously been shown to be more aggressive in a negative situation compared to those without it.
They called their hypothesis the "orchid/dandelion theory." Mothers with sensitive genes who needed a positive environment to be their best were like orchids, which only flourish when it is perfect for them. Those that remain the same throughout any environment, even though they may not reach the same highs and lows, were known as dandelions.
"The same gene that makes you look vulnerable in a bad situation makes you do better in a good environment. In a good environment, an orchid flourishes and is beautiful," co-author Irwin Garfinkel, a Columbia University researcher, told HealthDay. "But some of us, we're dandelions -- we might not thrive, but we can survive in all environments."
He added that while we can tell if a person has the T gene, whether or not we should work to get rid of it is another story.
"I think parents will wonder if they have the sensitive gene. If you have it, and you have a spouse, I think people need to take care to relax and watch one another's behavior," he explained. "But if this was only a bad gene, it would have died out. We have some evidence that there must be some advantage to having this gene."