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Polymorphisms in the oxytocin receptor gene are associated with the development of psychopathy

Published online by Cambridge University Press:  23 September 2013

Mark R. Dadds ,
Caroline Moul ,
Avril Cauchi ,
Carol Dobson-Stone ,
David J. Hawes ,
John Brennan ,
Ruth Urwin  and
Richard E. Ebstein
Mark R. Dadds*
Affiliation:
University of New South Wales
Caroline Moul
Affiliation:
University of New South Wales
Avril Cauchi
Affiliation:
University of New South Wales
Carol Dobson-Stone
Affiliation:
University of New South Wales Neuroscience Research Australia
David J. Hawes
Affiliation:
University of Sydney
John Brennan
Affiliation:
Sydney Children's Hospital
Ruth Urwin
Affiliation:
Children's Hospital at Westmead
Richard E. Ebstein
Affiliation:
National University of Singapore
*
Address correspondence and reprint requests to: Mark R. Dadds, School of Psychology, University of New South Wales, Sydney, NSW 2052, Australia; E-mail: m.dadds@unsw.edu.au.
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Abstract

The co-occurrence of child conduct problems (CPs) and callous–unemotional (CU) traits confers risk for psychopathy. The oxytocin (OXT) system is a likely candidate for involvement in the development of psychopathy. We tested variations in the OXT receptor gene (OXTR) in CP children and adolescents with varying levels of CU traits. Two samples of Caucasian children, aged 4–16 years, who met DSM criteria for disruptive behavior problems and had no features of autism spectrum disorder, were stratified into low versus high CU traits. Measures were the frequencies of nine candidate OXTR polymorphisms (single nucleotide polymorphisms). In Sample 1, high CU traits were associated with single nucleotide polymorphism rs1042778 in the 3′ untranslated region of OXTR and the CGCT haplotype of rs2268490, rs2254298, rs237889, and rs13316193. The association of rs1042778 was replicated in the second rural sample and held across gender and child versus adolescent age groups. We conclude that polymorphic variation of the OXTR characterizes children with high levels of CU traits and CPs. The results are consistent with a hypothesized role of OXT in the developmental antecedents of psychopathy, particularly the differential amygdala activation model of psychopathic traits, and add genetic evidence that high CU traits specify a distinct subgroup within CP children.

Type
Regular Articles
Information
Development and Psychopathology , Volume 26 , Issue 1 , February 2014 , pp. 21 - 31
Copyright
Copyright © Cambridge University Press 2013 

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