Research master thesis | Developmental Psychopathology in Education and Child Studies (research) (MSc)
open access
2016-01-01T00:00:00Z
Methylation of the serotonin transporter gene (5HTTLPR) might be one of the underlying molecular mechanisms of epigenetics through which effects of child maltreatment persist into adulthood. We...Show moreMethylation of the serotonin transporter gene (5HTTLPR) might be one of the underlying molecular mechanisms of epigenetics through which effects of child maltreatment persist into adulthood. We investigated how the experience of child maltreatment is associated with methylation density of 5HTTLPR and whether 5HTT genotype moderates this relation. The sample consisted of 22 females selected from the larger TwinPAD study (Out, Pieper, Bakermans-Kranenburg & Van IJzendoorn, 2010). DNA was obtained from buccal cells. The percentage of methylation in the first 245 bps was assessed using quantitative mass spectroscopy. Experiences of child maltreatment were established using the Adult Attachment Interview, coded with the Modified Maltreatment Classification System. We found that maltreatment severity was not significantly related to higher methylation density of 5HTTLPR, but the interaction of genotype with maltreatment severity significantly predicted methylation density. For carriers of the ss and sl genotype, more severe maltreatment was associated with higher methylation density, while for carriers of the ll genotype more severe maltreatment was associated with lower methylation density. We conclude that the relation between maltreatment severity and methylation density of 5HTTLPR is moderated by genotype, with ll carriers being protected against the methylating effects associated with maltreatment experiences. This study suggests that DNA methylation may be one of the molecular mechanism by which child maltreatment affects current and long-term functioning.Show less
