A longitudinal twin study of fears from middle childhood to early adulthood: evidence for a developmentally dynamic genome.

CONTEXT While the nature of common fears changes over development, we do not know whether genetic effects on fear-proneness are developmentally stable or developmentally dynamic. OBJECTIVE To determine the temporal pattern of genetic and environmental effects on the level of intensity of common fears. DESIGN Prospective, 4-wave longitudinal twin study. Structural modeling was performed with Mx. SETTING General community. PARTICIPANTS Two thousand four hundred ninety twins and their parents from the Swedish Twin Study of Child and Adolescent Development. MAIN OUTCOME MEASURE The level of parent- and/or self-reported fears obtained at ages 8 to 9, 13 to 14, 16 to 17, and 19 to 20 years. RESULTS Thirteen questionnaire items formed 3 distinct fear factors: situational, animal, and blood/injury. For all 3 fears, the best-fit model revealed developmentally dynamic effects and, in particular, evidence for both genetic attenuation and innovation. That is, genetic factors influencing fear intensity at age 8 to 9 years decline substantially in importance over time. Furthermore, new sets of genetic risk factors impacting fear intensity "come on line" in early adolescence, late adolescence, and early adulthood. As the twins aged, the influence of the shared environment declined and unique environment increased. No sex effects were found for situational fears while for animal and blood/injury fears, genetic factors in males and females were correlated but not identical. Shared environmental factors were both more important and more stable for animal fears than for situational or blood/injury fears. CONCLUSIONS Genetic effects on fear are developmentally dynamic from middle childhood to young adulthood. As children age, familial-environmental influences on fears decline in importance.

[1]  P. Levitt,et al.  Gene × Environment Effects: Stress and Memory Dysfunctions Caused by Stress and Gonadal Factor Irregularities during Puberty in Control And TGF-α Hypomorphic Mice , 2008, Neuropsychopharmacology.

[2]  M. Rutter,et al.  Etiological heterogeneity in the development of antisocial behavior: the Virginia Twin Study of Adolescent Behavioral Development and the Young Adult Follow-Up , 2007, Psychological Medicine.

[3]  Mike Rinck,et al.  Epidemiology of specific phobia subtypes: Findings from the Dresden Mental Health Study , 2007, European Psychiatry.

[4]  P. Lichtenstein,et al.  The Swedish Twin study of CHild and Adolescent Development: The TCHAD-Study , 2007, Twin Research and Human Genetics.

[5]  Michael Davis,et al.  The effect of gonadal hormones and gender on anxiety and emotional learning , 2006, Hormones and Behavior.

[6]  J. Armfield,et al.  Cognitive vulnerability: a model of the etiology of fear. , 2006, Clinical psychology review.

[7]  N. Martin,et al.  Longitudinal genetic analysis of plasma lipids. , 2006, Twin research and human genetics : the official journal of the International Society for Twin Studies.

[8]  S. Rabe-Hesketh,et al.  Prevalence and genetic and environmental influences on anxiety disorders in 6-year-old twins , 2005, Psychological Medicine.

[9]  J. Feldon,et al.  Mesolimbic dopaminergic pathways in fear conditioning , 2004, Progress in Neurobiology.

[10]  Kristian E Markon,et al.  An Empirical Comparison of Information-Theoretic Selection Criteria for Multivariate Behavior Genetic Models , 2004, Behavior genetics.

[11]  R. Plomin,et al.  A twin study of anxiety-related behaviours in pre-school children. , 2003, Journal of child psychology and psychiatry, and allied disciplines.

[12]  J. Sundet,et al.  Genetic and environmental causes of the interrelationships between self-reported fears. A study of a non-clinical sample of Norwegian identical twins and their families. , 2003, Scandinavian journal of psychology.

[13]  P. Lichtenstein,et al.  The Swedish Twin Registry: a unique resource for clinical, epidemiological and genetic studies , 2002, Journal of internal medicine.

[14]  K. Kendler,et al.  Sex differences in the genetic and environmental influences on the development of antisocial behavior , 2002, Development and Psychopathology.

[15]  Kenneth S Kendler,et al.  The etiology of phobias: an evaluation of the stress-diathesis model. , 2002, Archives of general psychiatry.

[16]  K. Kendler,et al.  Sex differences in genetic and environmental risk factors for irrational fears and phobias , 2002, Psychological Medicine.

[17]  M C Neale,et al.  A review and meta-analysis of the genetic epidemiology of anxiety disorders. , 2001, The American journal of psychiatry.

[18]  K. Kendler,et al.  The genetic epidemiology of irrational fears and phobias in men. , 2001, Archives of general psychiatry.

[19]  William D S Killgore,et al.  Sex-specific developmental changes in amygdala responses to affective faces , 2001, Neuroreport.

[20]  P. Lichtenstein,et al.  Heritability and prevalence of specific fears and phobias in childhood. , 2000, Journal of child psychology and psychiatry, and allied disciplines.

[21]  K. Bucholz,et al.  Social phobia in a population-based female adolescent twin sample: co-morbidity and associated suicide-related symptoms , 2000, Psychological Medicine.

[22]  A. Fyer,et al.  Current approaches to etiology and pathophysiology of specific phobia , 1998, Biological Psychiatry.

[23]  S. Taylor.  The hierarchic structure of fears. , 1998, Behaviour research and therapy.

[24]  R. Nesse,et al.  Fear and fitness: an evolu-tionary analysis of anxiety disorders , 1994 .

[25]  R. Kessler,et al.  A longitudinal twin study of 1-year prevalence of major depression in women. , 1993, Archives of general psychiatry.

[26]  D. Carmelli,et al.  Evidence for independent genetic influences on obesity in middle age. , 1992, International journal of obesity and related metabolic disorders : journal of the International Association for the Study of Obesity.

[27]  M. Cherner,et al.  Fears and fearfulness in children and adolescents: a genetic analysis of twin data. , 1992, Journal of child psychology and psychiatry, and allied disciplines.

[28]  R. Kessler,et al.  The genetic epidemiology of phobias in women. The interrelationship of agoraphobia, social phobia, situational phobia, and simple phobia. , 1992, Archives of general psychiatry.

[29]  R. Larson,et al.  Daily companionship in late childhood and early adolescence: changing developmental contexts. , 1991, Child development.

[30]  W. Ditto,et al.  A developmental-genetic analysis of common fears from early adolescence to early adulthood. , 1983, Child development.

[31]  D. Hartl,et al.  Principles of population genetics , 1981 .

[32]  S. Torgersen.  The Nature and Origin of Common Phobic Fears , 1979, British Journal of Psychiatry.

[33]  G. Schwarz.  Estimating the Dimension of a Model , 1978 .

[34]  R. Lande.  NATURAL SELECTION AND RANDOM GENETIC DRIFT IN PHENOTYPIC EVOLUTION , 1976, Evolution; international journal of organic evolution.

[35]  L. Derogatis,et al.  An Empirical Comparison of Three Indices of Factorial Similarity , 1972 .

[36]  M. Seligman.  Phobias and preparedness , 1971 .

[37]  P. Levitt,et al.  Gene x environment effects: stress and memory dysfunctions caused by stress and gonadal factor irregularities during puberty in control and TGF-alpha hypomorphic mice. , 2008, Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology.

[38]  W. Silverman,et al.  Specific phobia. , 2005, Child and adolescent psychiatric clinics of North America.

[39]  S. Rauch,et al.  Neural circuitry of anxiety: evidence from structural and functional neuroimaging studies. , 2003, Psychopharmacology bulletin.

[40]  H. Merckelbach,et al.  The Etiology of Childhood Specific Phobia , 2001 .

[41]  H Fischer,et al.  Gender and age differences in the prevalence of specific fears and phobias. , 1996, Behaviour research and therapy.

[42]  L. Cardon,et al.  Continuity and Change in General Cognitive Ability from 1 to 7 years of Age. , 1992 .

[43]  D. Boomsma,et al.  Simultaneous genetic analysis of longitudinal means and covariance structure using the simplex model: application to repeatedly measured weight in a sample of 164 female twins. , 1990, Acta geneticae medicae et gemellologiae.

[44]  K. Phillips,et al.  Path analysis of seven fear factors in adult twin and sibling pairs and their parents , 1987, Genetic epidemiology.

[45]  I. Marks.  Fears, phobias, and rituals , 1987 .

[46]  L. Ost.  Ways of acquiring phobias and outcome of behavioral treatments. , 1985, Behaviour research and therapy.

[47]  S. Rachman.  The conditioning theory of fear-acquisition: a critical examination. , 1977, Behaviour research and therapy.

[48]  S. Rachman.  The conditioning theory of fearacquisition: A critical examination , 1977 .