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Serotonin transporter linked polymorphic region (5-HTTLPR) genotype moderates the longitudinal impact of early caregiving on externalizing behavior

Published online by Cambridge University Press:  02 February 2015

Zoë H. Brett ,
Kathryn L. Humphreys ,
Anna T. Smyke ,
Mary Margaret Gleason ,
Charles A. Nelson ,
Charles H. Zeanah ,
Nathan A. Fox  and
Stacy S. Drury
Zoë H. Brett
Affiliation:
Tulane University
Kathryn L. Humphreys
Affiliation:
Tulane University
Anna T. Smyke
Affiliation:
Tulane University
Mary Margaret Gleason
Affiliation:
Tulane University
Charles A. Nelson
Affiliation:
Harvard University Children's Hospital Boston
Charles H. Zeanah
Affiliation:
Tulane University
Nathan A. Fox
Affiliation:
University of Maryland
Stacy S. Drury*
Affiliation:
Tulane University
*
Address correspondence and reprint requests to: Stacy S. Drury, Department of Psychiatry and Behavioral Sciences, 1430 Tulane Avenue, 8055, New Orleans, LA 70112; E-mail: sdrury@tulane.edu.
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Abstract

We examined caregiver report of externalizing behavior from 12 to 54 months of age in 102 children randomized to care as usual in institutions or to newly created high-quality foster care. At baseline no differences by group or genotype in externalizing were found. However, changes in externalizing from baseline to 42 months of age were moderated by the serotonin transporter linked polymorphic region genotype and intervention group, where the slope for short–short (S/S) individuals differed as a function of intervention group. The slope for individuals carrying the long allele did not significantly differ between groups. At 54 months of age, S/S children in the foster care group had the lowest levels of externalizing behavior, while children with the S/S genotype in the care as usual group demonstrated the highest rates of externalizing behavior. No intervention group differences were found in externalizing behavior among children who carried the long allele. These findings, within a randomized controlled trial of foster care compared to continued care as usual, indicate that the serotonin transporter linked polymorphic region genotype moderates the relation between early caregiving environments to predict externalizing behavior in children exposed to early institutional care in a manner most consistent with differential susceptibility.

Type
Special Section Articles
Information
Development and Psychopathology , Volume 27 , Issue 1: What Works for Whom? Genetic Moderation of Intervention Efficacy , February 2015 , pp. 7 - 18
Copyright
Copyright © Cambridge University Press 2015 

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