There are nearly one million substantiated reports of child maltreatment each year, according to the U.S. Department of Health and Human Services. Joan Kaufman, associate professor of psychiatry at Yale School of Medicine and author of the study, said many, but not all abused children develop chronic difficulties, particularly depression.
Previous studies have shown that a malfunction in the serotonin transporter gene is associated with the development of depression, but only in adults with histories of childhood maltreatment or recent stressful life events. After the release of serotonin from a cell into the synapse, this transporter takes the extra serotonin back into the cell so it is not degraded. In genetic pre-disposition to depression, fewer and less efficient transporter molecules are made.
The current study included 101 children, five-to-15 years old. Of that number, 57 were removed from their parents' care due to allegations of abuse and/or neglect, and 44 were children with no history of maltreatment or exposure to violence in the home.
Kaufman said the altered serotonin transporter gene was found in both maltreated children and those who were not maltreated, but was only associated with depression in children who had no positive supports. Social support was defined as someone a child could talk to about personal things, count on to buy the things they need, share good news with, get together with to have fun, and go to if they need advice.
"A lot of people think that maltreatment or having 'bad' genes leads inevitably to bad outcomes," Kaufman said. "This study demonstrates that this need not be the case, and that positive supports can help promote resiliency, even when there is maltreatment and a genetic predisposition for psychiatric illness."
Citation: Proceedings of the National Academy of Sciences, (November 15, 2004)