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Gene × Environment interaction and resilience: Effects of child maltreatment and serotonin, corticotropin releasing hormone, dopamine, and oxytocin genes

Published online by Cambridge University Press:  17 April 2012

Dante Cicchetti*
Affiliation:
Institute of Child Development, University of Minnesota Mt. Hope Family Center, University of Rochester
Fred A. Rogosch
Affiliation:
Mt. Hope Family Center, University of Rochester
*
Address correspondence and reprint requests to: Dante Cicchetti, Institute of Child Development, University of Minnesota, 51 East River Road, Minneapolis, MN 55455; E-mail: cicchett@umn.edu.

Abstract

In this investigation, gene–environment interaction effects in predicting resilience in adaptive functioning among maltreated and nonmaltreated low-income children (N = 595) were examined. A multicomponent index of resilient functioning was derived and levels of resilient functioning were identified. Variants in four genes (serotonin transporter linked polymorphic region, corticotropin releasing hormone receptor 1, dopamine receptor D4–521C/T, and oxytocin receptor) were investigated. In a series of analyses of covariance, child maltreatment demonstrated a strong negative main effect on children's resilient functioning, whereas no main effects for any of the genotypes of the respective genes were found. However, gene–environment interactions involving genotypes of each of the respective genes and maltreatment status were obtained. For each respective gene, among children with a specific genotype, the relative advantage in resilient functioning of nonmaltreated compared to maltreated children was stronger than was the case for nonmaltreated and maltreated children with other genotypes of the respective gene. Across the four genes, a composite of the genotypes that more strongly differentiated resilient functioning between nonmaltreated and maltreated children provided further evidence of genetic variations influencing resilient functioning in nonmaltreated children, whereas genetic variation had a negligible effect on promoting resilience among maltreated children. Additional effects were observed for children based on the number of subtypes of maltreatment children experienced, as well as for abuse and neglect subgroups. Finally, maltreated and nonmaltreated children with high levels of resilience differed in their average number of differentiating genotypes. These results suggest that differential resilient outcomes are based on the interaction between genes and developmental experiences.

Type
Special Section Articles
Copyright
Copyright © Cambridge University Press 2012

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References

Bakermans-Kranenburg, M. J., & van IJzendoorn, M. H. (2008). Oxytocin receptor (OXTR) and serotonin transporter (5-HTT) genes associated with observed parenting. Social Cognitive Affective Neuroscience, 3, 128134.CrossRefGoogle ScholarPubMed
Barnett, D., Manly, J. T., & Cicchetti, D. (1993). Defining child maltreatment: The interface between policy and research. In Cicchetti, D. & Toth, S. L. (Eds.), Child abuse, child development, and social policy (pp. 774). Norwood, NJ: Ablex.Google Scholar
Beeghly, M., & Cicchetti, D. (1994). Child maltreatment, attachment, and the self system: Emergence of an internal state lexicon in toddlers at high social risk. Development and Psychopathology, 6, 530.CrossRefGoogle Scholar
Belsky, J., Bakermans-Kranenburg, M. J., & Van IJzendoorn, M. H. (2007). For better and for worse: Differential susceptibility to environmental influences. Current Directions in Psychological Science, 16, 300304.CrossRefGoogle Scholar
Belsky, J., & Beaver, K. M. (2011). Cumulative-genetic plasticity, parenting and adolescent self-regulation. Journal of Child Psychology and Psychiatry, 52, 619626.CrossRefGoogle ScholarPubMed
Belsky, J., Jonassaint, C., Pluess, M., Stanton, M., Brummett, B., & Williams, R. (2009). Vulnerability genes or plasticity genes? Molecular Psychiatry, 14, 746754.CrossRefGoogle ScholarPubMed
Belsky, J., & Pluess, M. (2009). Beyond diathesis stress: Differential susceptibility to environmental influences. Psychological Bulletin, 135, 885908.CrossRefGoogle ScholarPubMed
Belsky, J., Schlomer, G. L., & Ellis, B. J. (2011). Beyond cumulative risk: Distinguishing harshness and unpredictability as determinants of parenting and early life history strategy. Developmental Psychology, 23, 8589.Google Scholar
Block, J., & Block, J. H. (1980). The role of ego-control and ego-resiliency in the organization of behavior. In Collins, W. A. (Ed.), The Minnesota symposia on child psychology: Development of cognition, affect, and social relations (Vol. 13, pp. 39101). Hillsdale, NJ: Erlbaum.Google Scholar
Bolger, K. E., Patterson, C. J., & Kupersmidt, J. B. (1998). Peer relationships and self-esteem among children who have been maltreated. Child Development, 69, 11711197.Google ScholarPubMed
Boyce, W. T., & Ellis, B. J. (2005). Biological sensitivity to context: I. An evolutionary–developmental theory of the origins and function of stress reactivity. Development and Psychopathology, 17, 271301.CrossRefGoogle ScholarPubMed
Bradley, B., Defife, J. A., Guarnaccia, C., Phifer, J., Fani, N., Ressler, K. J., et al. (2011). Emotion dysregulation and negative affect: Association with psychiatric symptoms. Journal of Clinical Psychiatry, 72, 685691.CrossRefGoogle ScholarPubMed
Bradley, R. G., Binder, E. B., Epstein, M. P., Tang, Y., Nair, H. P., Liu, W., et al. (2008). Influence of child abuse on adult depression: Moderation by the corticotrophin-releasing hormone receptor gene. Archives of General Psychiatry, 65, 190200.CrossRefGoogle Scholar
Caspi, A., Hariri, A., Holmes, A., Uher, R., & Moffitt, T. E. (2010). Genetic sensitivity to the environment: The case of the serotonin transporter gene (5-HTT) and its implications for studying complex diseases and traits. American Journal of Psychiatry, 167, 509527.CrossRefGoogle Scholar
Caspi, A., McClay, J., Moffitt, T., Mill, J., Martin, J., Craig, I. W., et al. (2002). Role of genotype in the cycle of violence in maltreated children. Science, 297, 851854.CrossRefGoogle ScholarPubMed
Caspi, A., Sugden, K., Moffitt, T. E., Taylor, A., Craig, I. W., Harrington, H. L., et al. (2003). Influence of life stress on depression: Moderation by a polymorphism in the 5-HTT gene. Science, 301, 386389.CrossRefGoogle ScholarPubMed
Charney, D. (2004). Psychobiological mechanisms of resilience and vulnerability: Implications for successful adaptation to extreme stress. American Journal of Psychiatry, 161, 195216.CrossRefGoogle ScholarPubMed
Cicchetti, D. (1984). The emergence of developmental psychopathology. Child Development, 55, 17.CrossRefGoogle ScholarPubMed
Cicchetti, D. (2003). Neuroendocrine functioning in maltreated children. In Cicchetti, D. & Walker, E. F. (Eds.), Neurodevelopmental mechanisms in psychopathology (pp. 345365). New York: Cambridge University Press.CrossRefGoogle Scholar
Cicchetti, D. (2010). Resilience under conditions of extreme stress: A multilevel perspective. World Psychiatry, 9, 110.CrossRefGoogle Scholar
Cicchetti, D., & Blender, J. A. (2006). A multiple-levels-of-analysis perspective on resilience: Implications for the developing brain, neural plasticity, and preventive interventions. Annals of the New York Academy of Sciences, 1094, 248258.CrossRefGoogle ScholarPubMed
Cicchetti, D., & Curtis, W. J. (2006). The developing brain and neural plasticity: Implications for normality, psychopathology, and resilience. In Cicchetti, D. & Cohen, D. J. (Eds.), Developmental psychopathology: Developmental neuroscience (Vol. 2, 2nd ed., pp. 164). Hoboken, NJ: Wiley.Google Scholar
Cicchetti, D., & Curtis, W. J. (2007). Multi-level perspectives on pathways to resilient functioning. Development and Psychopathology, 19, 627629.CrossRefGoogle Scholar
Cicchetti, D., & Dawson, G. (2002). Multiple levels of analysis. Development and Psychopathology, 14, 417420.CrossRefGoogle ScholarPubMed
Cicchetti, D., & Garmezy, N. (1993). Prospects and promises in the study of resilience. Development and Psychopathology, 5, 497502.CrossRefGoogle Scholar
Cicchetti, D., & Lynch, M. (1995). Failures in the expectable environment and their impact on individual development: The case of child maltreatment. In Cicchetti, D. & Cohen, D. J. (Eds.), Developmental psychopathology: Risk, disorder, and adaptation (Vol. 2, pp. 3271). Hoboken, NJ: Wiley.Google Scholar
Cicchetti, D., & Manly, J. T. (1990). A personal perspective on conducting research with maltreating families: Problems and solutions. In Brody, G. & Sigel, I. (Eds.), Methods of family research: Families at risk (Vol. 2, pp. 87133). Hillsdale, NJ: Erlbaum.Google Scholar
Cicchetti, D., & Rogosch, F. A. (1997). The role of self-organization in the promotion of resilience in maltreated children. Development and Psychopathology, 9, 799817.CrossRefGoogle ScholarPubMed
Cicchetti, D., & Rogosch, F. A. (2001). Diverse patterns of neuroendocrine activity in maltreated children. Development and Psychopathology, 13, 677694.CrossRefGoogle ScholarPubMed
Cicchetti, D., & Rogosch, F. A. (2007). Personality, adrenal steroid hormones, and resilience in maltreated children: A multilevel perspective. Development and Psychopathology, 19, 787809.CrossRefGoogle ScholarPubMed
Cicchetti, D., Rogosch, F. A., Gunnar, M. R., & Toth, S. L. (2010). The differential impacts of early abuse on internalizing problems and diurnal cortisol activity in school-aged children. Child Development, 25, 252269.CrossRefGoogle Scholar
Cicchetti, D., Rogosch, F. A., Lynch, M., & Holt, K. (1993). Resilience in maltreated children: Processes leading to adaptive outcome. Development and Psychopathology, 5, 629647.CrossRefGoogle Scholar
Cicchetti, D., Rogosch, F. A., & Oshri, A. (2011). Interactive effects of corticotropin releasing hormone receptor 1, serotonin transporter linked polymorphic region, and child maltreatment on diurnal cortisol regulation and internalizing symptomatology. Development and Psychopathology, 23, 11251138.CrossRefGoogle ScholarPubMed
Cicchetti, D., Rogosch, F. A., & Toth, S. L. (2011). The effects of child maltreatment and polymorphisms of the serotonin transporter and dopamine D4 receptor genes on infant attachment and intervention efficacy. Development and Psychopathology, 23, 357372.CrossRefGoogle ScholarPubMed
Cicchetti, D., & Toth, S. L. (1995). A developmental psychopathology perspective on child abuse and neglect. Journal of the American Academy of Child & Adolescent Psychiatry, 34, 541565.CrossRefGoogle ScholarPubMed
Cicchetti, D., Toth, S. L., & Manly, J. T. (2003). Maternal maltreatment interview. Unpublished manuscript.Google Scholar
Cicchetti, D., & Valentino, K. (2006). An ecological transactional perspective on child maltreatment: Failure of the average expectable environment and its influence upon child development. In Cicchetti, D. & Cohen, D. J. (Eds.), Developmental psychopathology (Vol. 3, 2nd ed., pp. 129201). Hoboken, NJ: Wiley.Google Scholar
Coie, J. D., & Dodge, K. A. (1983). Continuities and changes in children's social status: A five-year longitudinal study. Merrill–Palmer Quarterly, 29, 261282.Google Scholar
Collishaw, S., Pickles, A., Messer, J., Rutter, M., Shearer, C., & Maughan, B. (2007). Resilience to adult psychopathology following childhood maltreatment: Evidence from a community sample. Child Abuse & Neglect, 31, 211229.CrossRefGoogle ScholarPubMed
Curtis, W. J., & Cicchetti, D. (2003). Moving research on resilience into the 21st century: Theoretical and methodological considerations in examining the biological contributors to resilience. Development and Psychopathology, 15, 773810.CrossRefGoogle ScholarPubMed
Curtis, W. J., & Cicchetti, D. (2007). Emotion and resilience: A multilevel investigation of hemispheric electroencephalogram asymmetry and emotion regulation in maltreated and nonmaltreated children. Development and Psychopathology, 19, 811840.CrossRefGoogle ScholarPubMed
Davidson, R. J. (2000). Affective style, psychopathology, and resilience: Brain mechanisms and plasticity. American Psychologist, 55, 119.CrossRefGoogle ScholarPubMed
DeBellis, M. D. (2001). Developmental traumatology: The psychobiological development of maltreated children and its implications for research, treatment, and policy. Development and Psychopathology, 13, 539564.CrossRefGoogle Scholar
DeBellis, M. D. (2005). The psychobiology of neglect. Child Maltreatment, 10, 150172.CrossRefGoogle Scholar
DeYoung, C., Cicchetti, D., Rogosch, F. A., Gray, J., Eastman, M., & Grigorenko, E. (2011). Sources of cognitive exploration: Genetic variation in the prefrontal dopamine system predicts Openness/Intellect. Journal of Research in Personality, 45, 364371.CrossRefGoogle ScholarPubMed
DuMont, K. A., Widom, C. S., & Czaja, S. J. (2007). Predictors of resilience in abused and neglected children grown-up: The role of individual and neighborhood characteristics. Child Abuse & Neglect, 31, 255274.CrossRefGoogle ScholarPubMed
Duncan, L. E., & Keller, M. C. (2011). A critical review of the first ten years of candidate gene-by-environment interaction research in psychiatry. American Journal of Psychiatry, 168, 10411049.CrossRefGoogle Scholar
Egeland, B., Carlson, E. A., & Sroufe, L. A. (1993). Resilience as process. Development and Psychopathology, 5, 517528.CrossRefGoogle Scholar
Ellis, B. J., Boyce, W. T., Belsky, J., Bakermans-Kranenburg, M. J., & van IJzendoorn, M. H. (2011). Differential susceptibility to the environment: An evolutionary neurodevelopmental theory. Development and Psychopathology, 23, 728.CrossRefGoogle Scholar
English, D. J., Upadhyaya, M. P., Litrownik, A. J., Marshall, J. M., Runyan, D. K., Graham, J. C., et al. (2005). Maltreatment's wake: The relationship of maltreatment dimensions to child outcomes. Child Abuse & Neglect, 29, 597619.CrossRefGoogle ScholarPubMed
Feder, A., Nestler, E. J., & Charney, D. S. (2009). Psychobiology and molecular genetics of resilience. Nature Reviews Neuroscience, 10, 446457.CrossRefGoogle ScholarPubMed
Flores, E., Cicchetti, D., & Rogosch, F. A. (2005). Predictors of resilience in maltreated and nonmaltreated Latino children. Developmental Psychology, 41, 338351.CrossRefGoogle ScholarPubMed
Garmezy, N. (1970). Process and reactive schizophrenia: Some conceptions and issues. Schizophrenia Bulletin, 2, 3074.CrossRefGoogle Scholar
Garmezy, N. (1971). Vulnerability research and the issue of primary prevention. American Journal of Orthopsychiatry, 41, 101116.CrossRefGoogle ScholarPubMed
Garmezy, N. (1974a). Children at risk: Conceptual models and research methods. Schizophrenia Bulletin, 9, 55125.CrossRefGoogle Scholar
Garmezy, N. (1974b). Children at risk: The search for the antecedents of schizophrenia. Schizophrenia Bulletin, 8, 1490.CrossRefGoogle Scholar
Garmezy, N. (1974c). The study of competence in children at risk for severe psychopathology. In Anthony, E. J. & Koupernik, C. (Eds.), The child in his family: Vol. 3. Children at psychiatric risk (pp. 7797). New York: Wiley.Google Scholar
Garmezy, N., Masten, A. S., & Tellegen, A. (1984). The study of stress and competence in children: A building block for developmental psychopathology. Child Development, 55, 97111.CrossRefGoogle Scholar
Garmezy, N., & Rutter, M. (1983). Stress, coping and development in children. New York: McGraw–Hill.Google Scholar
Gelernter, J., Kranzler, H., & Cubells, J. F. (1997). Serotonin transporter protein (SLC6A4) allele and haplotype frequencies and linkage disequilibria in African- and European-American and Japanese populations and in alcohol-dependent subjects. Human Genetics, 101, 243246.CrossRefGoogle ScholarPubMed
Gottlieb, G. (1992). Individual development and evolution: The genesis of novel behavior. New York: Oxford University Press.Google Scholar
Gottlieb, G., & Halpern, C. T. (2002). A relational view of causality in normal and abnormal development. Development and Psychopathology, 14, 421436.CrossRefGoogle ScholarPubMed
Haskett, M. E., Nears, K., Ward, C., & McPherson, A. (2006). Diversity in adjustment of maltreated children: Predictors of resilient functioning. Clinical Psychology Review, 26, 796812.CrossRefGoogle Scholar
Inoue, T., Kimura, T., Azuma, C., Inazawa, J., Takemura, M., Kikuchi, T., et al. (1994). Structural organization of the human oxytocin receptor gene. Journal of Biological Chemistry, 269, 3245132456.CrossRefGoogle ScholarPubMed
Herrenkohl, E. C., Herrenkohl, R. C., & Egolf, M. (1994). Resilient early school-age children from maltreating homes: Outcomes in late adolescence. American Journal of Orthopsychiatry, 64, 301309.CrossRefGoogle ScholarPubMed
Jaffee, S. R., & Gallop, R. (2007). Social, emotional, and academic competence among children who have had contact with child protective services: Prevalence and stability estimates. Journal of the American Academy of Child & Adolescent Psychiatry, 46, 757765.CrossRefGoogle ScholarPubMed
Karg, K., Burmeister, M., Shedden, K., & Sen, S. (2011). The serotonin transporter promoter variant (5-HTTLPR), stress, and depression meta-analysis revisited: Evidence of genetic moderation. Archives of General Psychiatry, 68, 444454.CrossRefGoogle ScholarPubMed
Kim, J., & Cicchetti, D. (2004). A process model of mother–child relatedness and psychological adjustment among maltreated and nonmaltreated children: The role of self-esteem and social competence. Journal of Abnormal Child Psychology, 32, 341354.CrossRefGoogle Scholar
Kim-Cohen, J., & Gold, A. L. (2009). Measured gene–environment interactions and mechanisms promoting resilient development. Current Directions in Psychological Science, 18, 138142.CrossRefGoogle Scholar
Kovacs, M. (1982, 1992). The children's depression inventory: A self-rated depression scale for school-aged youngsters. Pittsburgh, PA: University of Pittsburgh.Google Scholar
Lesch, K. P., Bengel, D., Heils, A., Sabol, S. Z., Greenberg, B. D., Petri, S., et al. (1996). Association of anxiety-related traits with a polymorphism in the serotonin transporter gene regulatory region. Science, 274, 15271531.CrossRefGoogle ScholarPubMed
Luthar, S. S. (2006). Resilience in development: A synthesis of research across five decades. In Cicchetti, D. & Cohen, D. (Eds.), Developmental psychopathology: Vol. 3. Risk, disorder, and adaptation (2nd ed., pp. 739795). Hoboken, NJ: Wiley.Google Scholar
Luthar, S. S., Cicchetti, D., & Becker, B. (2000). The construct of resilience: A critical evaluation and guidelines for future work. Child Development, 71, 543562.CrossRefGoogle ScholarPubMed
Manly, J. T. (2005). Advances in research definitions of child maltreatment. Child Abuse & Neglect, 29, 425439.CrossRefGoogle Scholar
Manly, J. T., Cicchetti, D., & Barnett, D. (1994). The impact of subtype, frequency, chronicity, and severity of child maltreatment on social competence and behavior problems. Development and Psychopathology, 6, 121143.CrossRefGoogle Scholar
Manly, J. T., Kim, J. E., Rogosch, F. A., & Cicchetti, D. (2001). Dimensions of child maltreatment and children's adjustment: Contributions of developmental timing and subtype. Development and Psychopathology, 13, 759782.CrossRefGoogle ScholarPubMed
Masten, A. S. (1986). Humor and competence in school-aged children. Child Development, 57, 461473.CrossRefGoogle ScholarPubMed
Masten, A. S. (2001). Ordinary magic: Resilience processes in development. American Psychologist, 56, 227238.CrossRefGoogle ScholarPubMed
Masten, A. S. (Ed.). (2007). Multilevel dynamics in developmental psychopathology: The Minnesota symposia on child psychology (Vol. 34). Mahwah, NJ: Erlbaum.CrossRefGoogle Scholar
Masten, A. S. (2011). Resilience in children threatened by extreme adversity: Frameworks for research, practice, and translational synergy. Development and Psychopathology, 23, 141154.CrossRefGoogle ScholarPubMed
Masten, A. S. (in press). Risk and resilience in development. In Zelazo, P. D. (Ed.), Oxford handbook of developmental psychology. New York: Oxford University Press.Google Scholar
Masten, A. S., Best, K., & Garmezy, N. (1990). Resilience and development: Contributions from the study of children who overcome adversity. Development and Psychopathology, 2, 425444.CrossRefGoogle Scholar
Masten, A. S., & Garmezy, N. (1985). Risk, vulnerability, and protective factors in developmental psychopathology. In Lahey, B. & Kazdin, A. (Eds.), Advances in clinical child psychology (Vol. 8, pp. 152). New York: Plenum Press.Google Scholar
McGloin, J. M., & Widom, C. S. (2001). Resilience among abused and neglected children grown up. Development and Psychopathology, 13, 10211038.CrossRefGoogle ScholarPubMed
Miller, G. E., Chen, E., & Parker, K. J. (2011). Psychological stress in childhood and susceptibility to the chronic diseases of aging: Moving towards a model of behavioral and biological mechanisms. Psychological Bulletin, 137, 959997.CrossRefGoogle Scholar
Moran, P. B., & Eckenrode, J. (1992). Protective personality characteristics among adolescent victims of maltreatment. Child Abuse and Neglect, 16, 743754.CrossRefGoogle ScholarPubMed
Pekarik, E. G., Prinz, R. J., Liebert, D. E., Weintraub, S., & Neale, J. M. (1976). The Pupil Evaluation Inventory: A sociometric technique for assessing children's social behavior. Journal of Abnormal Child Psychology, 4, 8397.CrossRefGoogle ScholarPubMed
Polanczyk, G., Avshalom, C., Williams, B., Price, T. S., Danese, A., Sugden, K., et al. (2009). Protective effect of CRHR1 gene variants on the development of adult depression following childhood maltreatment. Archives of General Psychiatry, 66, 978985.CrossRefGoogle ScholarPubMed
Risch, N., Herrell, R., Lehner, T., Liang, K. Y., Eaves, L., Hoh, J., et al. (2009). Interaction between the serotonin transporter gene (5-HTTLPR), stressful life events, and risk of depression: A meta-analysis. Journal of the American Medical Association, 301, 24622471.CrossRefGoogle ScholarPubMed
Rutter, M. (1986). Child psychiatry: The interface between clinical and developmental research. Psychological Medicine, 16, 151160.CrossRefGoogle ScholarPubMed
Rutter, M. (1987). Psychosocial resilience and protective mechanisms. American Journal of Orthopsychiatry, 57, 316331.CrossRefGoogle ScholarPubMed
Rutter, M. (2012). Resilience as a dynamic concept. Development and Psychopathology, 24, 335344.CrossRefGoogle ScholarPubMed
Rutter, M., & Garmezy, N. (1983). Developmental psychopathology. In Hetherington, E. M. (Ed.), Handbook of child psychology (Vol. 4, 4th ed., pp. 774911). New York: Wiley.Google Scholar
Sameroff, A. J. (1983). Developmental systems: Contexts and evolution. In Mussen, P. (Ed.), Handbook of child psychology (Vol. 1, pp. 237294). New york: Wiley.Google Scholar
Saphire-Bernstein, S., Way, B. M., Kim, H. S., Sherman, D. K., & Taylor, S. E. (2011). Oxytocin receptor gene (OXTR) is related to psychological resources. Proceedings of the National Academy of Sciences of the United States of America, 108, 1511815122.CrossRefGoogle ScholarPubMed
Sedlak, A. J., Mettenburg, J., Basena, M., Petta, I., McPherson, K., Greene, A., et al. (2010). Fourth national incidence study of child abuse and neglect (NIS–4): Report to Congress, Executive Summary. Washington, DC: US Department of Health and Human Services, Administration for Children and Families.Google Scholar
Seligman, M. E. P., & Csikszentmihalyi, M. (2000). Positive psychology: An introduction. American Psychologist, 55, 514.CrossRefGoogle ScholarPubMed
Sonuga-Barke, E. J. S., Oades, R. D., Psychogiou, L.Chen, W., Franke, B., Buitelaar, J., et al. (2009). Dopamine and serotonin transporter genotypes moderate sensitivity to maternal expressed emotion: The case of conduct and emotional problems in attention deficit/hyperactivity disorder. Journal of Child Psychology and Psychiatry, 9, 10521063.CrossRefGoogle Scholar
The National Longitudinal Study of Adolescent Health. (n.d.). Add Health system to code race and ethnicity in a single variable. Retrieved from http://www.cpc.unc.edu/projects/addhealth/data/code/race. University of North Carolina, Chapel Hill, Carolina Population Center.Google Scholar
Waddington, C. H. (1957). The strategy of genes. London: Allen & Unwin.Google Scholar
Warnes, G. (2003). GeneticsBase. The genetics package: Utilities for handling genetic data. Research News, 3.Google Scholar
Werner, E., & Smith, R. (1982). Vulnerable but invincible: A study of resilient children. New York: McGraw–Hill.Google Scholar
Werner, E., & Smith, R. (1992). Overcoming the odds: High-risk children from birth to adulthood. Ithaca, NY: Cornell University Press.CrossRefGoogle Scholar
Wingo, A. P., Fani, N., Bradley, B., & Ressler, K. J. (2010). Psychological resilience and neurocognitive performance in a traumatized community sample. Depression and Anxiety, 27, 768774.CrossRefGoogle Scholar
Wright, J. (1983). The structure and perception of behavioral consistency. Doctoral dissertation, Stanford University.Google Scholar