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Thursday, August 22, 2013

An unexpected consequence of the Great Recession

A great many people were adversely affected by the 2008 recession. Among the people affected were young children, but not just for the reasons you might think. Obviously, children are affected when their parents lose their jobs, their health insurance, and/or their homes. But it turns out that beyond all that, the poor economic climate also made one group of women into harsher mothers.

It’s well documented that mothers parent less well under conditions of stress. This is seen in the primate as well as the human world. The worst environments for parents seem to be those that fluctuate seemingly randomly between bad and good times, suggesting that uncertainty is the worst stressor of all.

There also appear to be genetic components to how well parents handle stress. In particular, the DRD2 gene, which normally encodes part of a dopamine receptor, has a mutant variation (a T in place of a C at a specific site) that results in that individual having fewer dopamine receptors in her brain. In other words, people with the T version have a dampened response to the normal release of the neurotransmitter dopamine

Dohoon Lee from New York University plus researchers from several other institutions wondered whether there was a correlation between increasingly harsh parenting during bad economic times and having a mutated DRD2 gene. They used the Fragile Families and Child Wellbeing Study as their data source. This study collected information on nearly 5000 children born in 20 large U.S. cities between 1998-2000. The mothers, three quarters of whom were single at the start of the study, were interviewed at the birth of their child, and then again when that child was 1, 3, 5 and 9 years old. Thus, the last data point occurred either right before or soon after the start of the recession. The interviews included ten criteria, half physical and half psychological, to gauge how harshly the children were treated by their mothers. The women also provided saliva samples to determine their DRD2 type.

As the unemployment rate increased, mothers became more harsh with their children. Interestingly, this correlation was not seen with high levels of unemployment, just with changes in those levels, again suggesting that the anticipation of trouble was worse than actual adversity. The affect was much stronger in women with the T version of DRD2 than in those with the C version. Women with the T allele also did not show as much lessening of harshness once times began to improve.

So, if this study is accurate, parenting is adversely affected by poor economic conditions, and women with a particular genotype are especially sensitive to those conditions.

A couple of things about this. First, at this point, we only have an interesting correlation. We can’t yet say that poor economic conditions make mothers treat their children more severely. Second, we definitely can’t say that economic conditions or DRD2 alleles only affect women. This study only interviewed mothers, but there’s no reason to think that men aren’t equally affected.

Dohoon Lee, Jeanne Brooks-Gunn, Sara S. McLanahan, Daniel Notterman, & Irwin Garfinkel (2013). The Great Recession, genetic sensitivity, and maternal harsh parenting Proceedings of the National Academy of Sciences : doi: 10.1073/pnas.1312398110.