Increased serotonin transporter gene (SERT) DNA methylation is associated with bullying victimization and blunted cortisol response to stress in childhood: A longitudinal study of discordant monozygotic twins

Psychological Medicine

Volumn 43, Issue 9, 2013, Pages 1813-1823

  Ouellet Morin, I ^a,b   Wong, C C Y ^a   Danese, A ^a   Pariante, C M ^a   Papadopoulos, A S ^a,c   Mill, J ^a   Arseneault, L ^a  

^a KING'S COLLEGE LONDON   (United Kingdom)

^b UNIVERSITÉ DE MONTRÉAL   (Canada)

^c BETHLEM ROYAL HOSPITAL   (United Kingdom)

Author keywords

Bullying; childhood victimization; cortisol; DNA methylation; hypothalamic pituitary adrenal axis; SERT

Indexed keywords

HYDROCORTISONE; SEROTONIN TRANSPORTER; SLC6A4 PROTEIN, HUMAN;

ARTICLE; BULLYING; CHILD; CRIME VICTIM; DNA METHYLATION; FEMALE; GENETICS; HUMAN; HYPOPHYSIS ADRENAL SYSTEM; HYPOTHALAMUS HYPOPHYSIS SYSTEM; LONGITUDINAL STUDY; MALE; MENTAL STRESS; METABOLISM; MONOZYGOTIC TWINS; PHYSIOLOGY; PSYCHOLOGICAL ASPECT; SOCIAL ENVIRONMENT; TWINS; PSYCHOLOGY;

BULLYING; CHILD; CRIME VICTIMS; DNA METHYLATION; FEMALE; HUMANS; HYDROCORTISONE; HYPOTHALAMO-HYPOPHYSEAL SYSTEM; LONGITUDINAL STUDIES; MALE; PITUITARY-ADRENAL SYSTEM; SEROTONIN PLASMA MEMBRANE TRANSPORT PROTEINS; SOCIAL ENVIRONMENT; STRESS, PSYCHOLOGICAL; TWINS, MONOZYGOTIC;

EID: 84881430062     PISSN: 00332917     EISSN: 14698978     Source Type: Journal    
DOI: 10.1017/S0033291712002784     Document Type: Article

References (95)

1. Alexander N, Kuepper Y, Schmitz A, Osinsky R, Kozyra E, Hennig J (2009). Gene-environment interactions predict cortisol responses after acute stress : Implications for the etiology of depression. Psychoneuroendocrinology 34, 1294-1303.
2. Arseneault L, Bowes L, Shakoor S (2010). Bullying victimization in youths and mental health problems: 'Much ado about nothing ' ? Psychological Medicine 40, 717-729.
3. Arseneault L, Cannon M, Fisher HL, Polanczyk G, Moffitt TE, Caspi A (2011). Childhood trauma and children's emerging psychotic symptoms: A genetically sensitive longitudinal cohort study. American Journal of Psychiatry 168, 65-72.
4. Bagot RC, Meaney MJ (2010). Epigenetics and the biological basis of gene x environment interactions. Journal of the American Academy of Child and Adolescent Psychiatry 49, 752-771.
5. Bakermans-Kranenburg MJ, van IJzendoorn MH (2009). The first 10,000 Adult Attachment Interviews : Distributions of adult attachment representations in clinical and non-clinical groups. Attachment and Human Development 11, 223-263.
6. Ball HA, Arseneault L, Taylor A, Maughan B, Caspi A, Moffitt TE (2008). Genetic and environmental influences on victims, bullies and bully-victims in childhood. Journal of Child Psychology and Psychiatry 49, 104-112.
7. Beach SR, Brody GH, Todorov AA, Gunter TD, Philibert RA (2010). Methylation at SLC6A4 is linked to family history of child abuse: An examination of the Iowa Adoptee sample. American Journal of Medical Genetics : Part B Neuropsychiatric Genetics 153B, 710-713.
8. Beach SR, Brody GH, Todorov AA, Gunter TD, Philibert RA (2011). Methylation at 5HTT mediates the impact of child sex abuse on women's antisocial behavior : An examination of the Iowa adoptee sample. Psychosomatic Medicine 73, 83-87.
9. Bouma E, Riese H, Nederhof E, Ormel J, Oldehinkel A (2010). No replication of genotype effect of 5-HTTLPR on cortisol response to social stress in larger adolescent sample. Biological Psychiatry 68, e33-e34.
10. Bruce J, Fisher PA, Pears KC, Levine S (2009). Morning cortisol levels in preschool-aged foster children : Differential effects of maltreatment type. Developmental Psychobiology 51, 14-23.
11. Buske-Kirschbaum A, Jobst S, Wustmans A, Kirschbaum C, Rauh W, Hellhammer D (1997). Attenuated free cortisol response to psychosocial stress in children with atopic dermatitis. Psychosomatic Medicine 59, 419-426. (Pubitemid 27315244)
12. Byun HM, Siegmund KD, Pan F, Weisenberger DJ, Kanel G, Laird PW, Yang AS (2009). Epigenetic profiling of somatic tissues from human autopsy specimens identifies tissue-and individual-specific DNA methylation patterns. Human Molecular Genetics 18, 4808-4817.
13. Canli T, Lesch KP (2007). Long story short : The serotonin transporter in emotion regulation and social cognition. Nature Neuroscience 10, 1103-1109. (Pubitemid 47339957)
14. Carpenter LL, Carvalho JP, Tyrka AR, Wier LM, Mello AF, Mello MF, Anderson GM, Wilkinson CW, Price LH (2007). Decreased adrenocorticotropic hormone and cortisol responses to stress in healthy adults reporting significant childhood maltreatment. Biological Psychiatry 62, 1080-1087. (Pubitemid 350029729)
15. Caspi A, Hariri AR, Holmes A, Uher R, Moffitt TE (2010). Genetic sensitivity to the environment: The case of the serotonin transporter gene and its implications for studying complex diseases and traits. American Journal of Psychiatry 167, 509-527.
16. Champagne FA (2010). Epigenetic influence of social experiences across the lifespan. Developmental Psychobiology 52, 299-311.
17. Cicchetti D, Rogosch FA (2001). Diverse patterns of neuroendocrine activity in maltreated children. Development and Psychopatholgy 13, 677-693. (Pubitemid 33406349)
18. Coolen MW, Statham AL, Gardiner-Garden M, Clark SJ (2007). Genomic profiling of CpG methylation and allelic specificity using quantitative high-throughput mass spectrometry : Critical evaluation and improvements. Nucleic Acids Research 35, e119.
19. Devlin AM, Brain U, Austin J, Oberlander TF (2010). Prenatal exposure to maternal depressed mood and the MTHFR C677T variant affect SLC6A4 methylation in infants at birth. PLoS One 5, e12201.
20. Dickerson SS, Kemeny ME (2004). Acute stressors and cortisol responses : A theoretical integration and synthesis of laboratory research. Psychological Bulletin 130, 355-391. (Pubitemid 38614661)
21. Dozier M, Manni M, Gordon MK, Peloso E, Gunnar MR, Stovall-McClough KC, Eldreth D, Levine S (2006). Foster children's diurnal production of cortisol : An exploratory study. Child Maltreatment 11, 189-197. (Pubitemid 43529072)
22. Dyche G, Johnson D (1991). Development and evaluation of CHIPASAT, an attentional test for children : II test-retest reliability and practice effect for a normal sample. Perceptual and Motor Skills 72, 563-572.
23. Elzinga BM, Roelofs K, Tollenaar MS, Bakvis P, van Pelt J, Spinhoven P (2008). Diminished cortisol responses to psychosocial stress associated with lifetime adverse events : A study among healthy young subjects. Psychoneuroendocrinology 33, 227-237.
24. Essex MJ, Boyce TW, Hertzman C, Lam LL, Armstrong JM, Neumann SM, Kobor MS (2011). Epigenetic vestiges of early developmental adversity : Childhood stress exposure and DNA methylation in adolescence. Child Development. Published online : 2 September 2011. doi :10.1111/j.1467-8624.2011.01641.x.
25. Fairchild G, van Goozen SH, Stollery SJ, Brown J, Gardiner J, Herbert J, Goodyer IM (2008). Cortisol diurnal rhythm and stress reactivity in male adolescents with early-onset or adolescence-onset conduct disorder. Biological Psychiatry 64, 599-606.
26. Feder A, Nestler EJ, Charney DS (2009). Psychobiology and molecular genetics of resilience. Nature Reviews Neuroscience 10, 446-457.
27. Feinberg AP (2008). Epigenetics at the epicenter of modern medicine. Journal of the American Medical Association 299, 1345-1350. (Pubitemid 351439080)
28. Filiberto AC, Maccani MA, Koestler D, Wilhelm-Benartzi C, Avissar-Whiting M, Banister CE, Gagne LA, Marsit CJ (2011). Birthweight is associated with DNA promoter methylation of the glucocorticoid receptor in human placenta. Epigenetics 6, 566-572.
29. Francis DD, Champagne FA, Liu D, Meaney MJ (1999). Maternal care, gene expression, and the development of individual differences in stress reactivity. Annals of the New York Academy of Sciences 896, 66-84. (Pubitemid 30040239)
30. Freeman B, Smith N, Curtis C, Huckett L, Mill J, Craig IW (2003). DNA from buccal swabs recruited by mail : Evaluation of storage effects on long-term stability and suitability for multiplex polymerase chain reaction genotyping. Behavior Genetics 33, 67-72. (Pubitemid 36176783)
31. Fries E, Hesse J, Hellhammer J, Hellhammer DH (2005). A new view on hypocortisolism. Psychoneuroendocrinology 30, 1010-1016. (Pubitemid 40982486)
32. Gotlib IH, Joormann J, Minor KL, Hallmayer J (2008). HPA axis reactivity : A mechanism underlying the associations among 5-HTTLPR, stress, and depression. Biological Psychiatry 63, 847-851. (Pubitemid 351458452)
33. Gunnar MR, Vazquez DM (2001). Low cortisol and a flattening of expected daytime rhythm: Potential indices of risk in human development. Development and Psychopathology 13, 515-538. (Pubitemid 33406341)
34. Hariri AR, Mattay VS, Tessitore A, Kolachana B, Fera F, Goldman D, Egan MF, Weinberger DR (2002). Serotonin transporter genetic variation and the response of the human amygdala. Science 297, 400-403. (Pubitemid 34790769)
35. Heijmans BT, Tobi EW, Stein AD, Putter H, Blauw GJ, Susser ES, Slagboom PE, Lumey LH (2008). Persistent epigenetic differences associated with prenatal exposure to famine in humans. Proceedings of the National Academy of Sciences USA 105, 17046-17049.
36. Heim C, Ehlert U, Hellhammer DH (2000). The potential role of hypocortisolism in the pathophysiology of stress-related bodily disorders. Psychoneuroendocrinology 25, 1-35. (Pubitemid 29490865)
37. Herman JP, Cullinan WE (1997). Neurocircuitry of stress : Central control of the hypothalamo-pituitary-adrenocortical axis. Trends in Neurosciences 20, 78-84. (Pubitemid 27050702)
38. Illingworth R, Kerr A, Desousa D, Jorgensen H, Ellis P, Stalker J, Jackson D, Clee C, Plumb R, Rogers J, Humphray S, Cox T, Langford C, Bird A (2008). A novel CpG island set identifies tissue-specific methylation at developmental gene loci. PLoS Biology 6, e22.
39. Jirtle RL, Skinner MK (2007). Environmental epigenomics and disease susceptibility. Nature Reviews Genetics 8, 253-262. (Pubitemid 46439287)
40. Johnstone SE, Baylin SB (2010). Stress and the epigenetic landscape : A link to the pathobiology of human diseases ? Nature Reviews Genetics 11, 806-812.
41. Kinnally EL, Capitanio JP, Leibel R, Deng L, Leduc C, Haghighi F, Mann JJ (2010a). Epigenetic regulation of serotonin transporter expression and behavior in infant rhesus macaques. Genes, Brain and Behavior 9, 575-582.
42. Kinnally EL, Tarara ER, Mason WA, Mendoza SP, Abel K, Lyons LA, Capitanio JP (2010b). Serotonin transporter expression is predicted by early life stress and is associated with disinhibited behavior in infant rhesus macaques. Genes, Brain and Behavior 9, 45-52.
43. Lesch KP, Bengel D, Heils A, Sabol SZ, Greenberg BD, Petri S, Benjamin J, Muller CR, Hamer DH, Murphy DL (1996). Association of anxiety-related traits with a polymorphism in the serotonin transporter gene regulatory region. Science 274, 1527-1531. (Pubitemid 26403928)
44. Levine S (2005). Developmental determinants of sensitivity and resistance to stress. Psychoneuroendocrinology 30, 939-946. (Pubitemid 40982476)
45. Li Q, Wichems C, Heils A, Van De Kar LD, Lesch KP, Murphy DL (1999). Reduction of 5-hydroxytryptamine (5-HT)1A-mediated temperature and neuroendocrine responses and 5-HT1A binding sites in 5-HT transporter knockout mice. Journal of Pharmacology and Experimental Therapeutics 291, 999-1007.
46. Liu D, Diorio J, Tannenbaum B, Caldji C, Francis D, Freedman A, Sharma S, Pearson D, Plotsky PM, Meaney MJ (1997). Maternal care, hippocampal glucocorticoid receptors, and hypothalamic-pituitary-adrenal responses to stress. Science 277, 1659-1662. (Pubitemid 27446227)
47. Lowry CA (2002). Functional subsets of serotonergic neurones: Implications for control of the hypothalamic-pituitary-adrenal axis. Journal of Neuroendocrinology 14, 911-923. (Pubitemid 35378709)
48. Lupien SJ, McEwen BS, Gunnar MR, Heim C (2009). Effects of stress throughout the lifespan on the brain, behaviour and cognition. Nature Reviews Neuroscience 10, 434-445.
49. McCrory E, De Brito SA, Viding E (2010). Research review: The neurobiology and genetics of maltreatment and adversity. Journal of Child Psychology and Psychiatry 51, 1079-1095.
50. McGowan PO, Sasaki A, D'Alessio AC, Dymov S, Labonte B, Szyf M, Turecki G, Meaney MJ (2009). Epigenetic regulation of the glucocorticoid receptor in human brain associates with childhood abuse. Nature Reviews Neuroscience 12, 342-348.
51. McGowan PO, Szyf M (2010). The epigenetics of social adversity in early life : Implications for mental health outcomes. Neurobiology of Disease 39, 66-72.
52. Meaney MJ (2010). Epigenetics and the biological definition of gene x environment interactions. Child Development 81, 41-79.
53. Meaney MJ, Szyf M (2005). Environmental programming of stress responses through DNA methylation : Life at the interface between a dynamic environment and a fixed genome. Dialogues in Clinical Neurosciences 7, 103-123. (Pubitemid 40961531)
54. Meewisse ML, Reitsma JB, de Vries GJ, Gersons BP, OlffM (2007). Cortisol and post-traumatic stress disorder in adults : Systematic review and meta-analysis. British Journal of Psychiatry 191, 387-392. (Pubitemid 350069578)
55. Mill J, Petronis A (2007). Molecular studies of major depressive disorder : The epigenetic perspective. Molecular Psychiatry 12, 799-814. (Pubitemid 47347791)
56. Miller GE, Chen E, Zhou ES (2007). If it goes up, must it come down? Chronic stress and the hypothalamic-pituitary-adrenocortical axis in humans. Psychological Bulletin 133, 25-45.
57. Miller JM, Kinnally EL, Ogden RT, Oquendo MA, Mann JJ, Parsey RV (2009). Reported childhood abuse is associated with low serotonin transporter binding in vivo in major depressive disorder. Synapse 63, 565-573.
58. Moffitt TE; the E-Risk Study Team (2002). Teen-aged mothers in contemporary Britain. Journal of Child Psychology and Psychiatry 43, 727-742. (Pubitemid 36943922)
59. Mondelli V, Dazzan P, Hepgul N, Di Forti M, Aas M, D'Albenzio A, Di Nicola M, Fisher H, Handley R, Marques TR, Morgan C, Navari S, Taylor H, Papadopoulos A, Aitchison KJ, Murray RM, Pariante CM (2010). Abnormal cortisol levels during the day and cortisol awakening response in first-episode psychosis : The role of stress and of antipsychotic treatment. Schizophrenia Research 116, 234-242.
60. Monteiro J, Derom C, Vlietinck R, Kohn N, Lesser M, Gregersen PK (1998). Commitment to X inactivation precedes the twinning event in monochorionic MZ twins. American Journal of Human Genetics 63, 339-346. (Pubitemid 30418615)
61. Mueller A, Brocke B, Fries E, Lesch KP, Kirschbaum C (2010). The role of the serotonin transporter polymorphism for the endocrine stress response in newborns. Psychoneuroendocrinology 35, 289-296.
62. Murgatroyd C, Patchev AV, Wu Y, Micale V, Bockmuhl Y, Fischer D, Holsboer F, Wotjak CT, Almeida OF, Spengler D (2009). Dynamic DNA methylation programs persistent adverse effects of early-life stress. Nature Reviews Neuroscience 12, 1559-1566.
63. Naumova OY, Lee M, Koposov R, Szyf M, Dozier M, Grigorenko EL (2011). Differential patterns of wholegenome DNA methylation in institutionalized children and children raised by their biological parents. Development and Psychopathology 24, 143-155.
64. Oberlander TF, Weinberg J, Papsdorf M, Grunau R, Misri S, Devlin AM (2008). Prenatal exposure to maternal depression, neonatal methylation of human glucocorticoid receptor gene (NR3C1) and infant cortisol stress responses. Epigenetics 3, 97-106.
65. Ochsner KN, Gross JJ (2005). The cognitive control of emotion. Trends in Cognitive Sciences 9, 242-249. (Pubitemid 40615112)
66. Olsson CA, Foley DL, Parkinson-Bates M, Byrnes G, McKenzie M, Patton GC, Morley R, Anney RJ, Craig JM, Saffery R (2010). Prospects for epigenetic research within cohort studies of psychological disorder : A pilot investigation of a peripheral cell marker of epigenetic risk for depression. Biological Psychology 83, 159-165.
67. Ouellet-Morin I, Danese A, Bowes L, Shakoor S, Ambler A, Pariante C, Papadopoulos A, Caspi A, Moffitt TE, Arseneault L (2011a). A discordant MZ twin design shows blunted cortisol reactivity among bullied children. Journal of the American Academy of Child and Adolescent Psychiatry 50, 574-582.
68. Ouellet-Morin I, Odgers C, Danese A, Bowes L, Shakoor S, Papadopoulos A, Caspi A, Moffitt TE, Arseneault L (2011b). Blunted cortisol responses to stress signal social and behavioral problems among maltreated/bullied 12 year-old children. Biological Psychiatry 70, 1016-1023.
69. Pezawas L, Meyer-Lindenberg A, Drabant EM, Verchinski BA, Munoz KE, Kolachana BS, Egan MF, Mattay VS, Hariri AR, Weinberger DR (2005). 5-HTTLPR polymorphism impacts human cingulate-amygdala interactions : A genetic susceptibility mechanism for depression. Nature Neuroscience 8, 828-834. (Pubitemid 43085851)
70. Philibert RA, Sandhu H, Hollenbeck N, Gunter T, Adams W, Madan A (2008). The relationship of 5HTT (SLC6A4) methylation and genotype on mRNA expression and liability to major depression and alcohol dependence in subjects from the Iowa Adoption Studies. American Journal of Medical Genetics : Part B Neuropsychiatric Genetics 147B, 543-549. (Pubitemid 351961655)
71. Price TS, Freeman B, Craig I, Petrill SA, Ebersole L, Plomin R (2000). Infant zygosity can be assigned by parental report questionnaire data. Twin Research 3, 129-133.
72. Pruessner JC, Kirschbaum C, Meinlschmid G, Hellhammer DH (2003). Two formulas for computation of the area under the curve represent measures of total hormone concentration versus time-dependent change. Psychoneuroendocrinology 28, 916-931. (Pubitemid 36936799)
73. Rakyan VK, Down TA, Balding DJ, Beck S (2011). Epigenome-wide association studies for common human diseases. Nature Reviews Genetics 12, 529-541.
74. Rakyan VK, Down TA, Thorne NP, Flicek P, Kulesha E, Graf S, Tomazou EM, Backdahl L, Johnson N, Herberth M, Howe KL, Jackson DK, Miretti MM, Fiegler H, Marioni JC, Birney E, Hubbard TJ, Carter NP, Tavare S, Beck S (2008). An integrated resource for genome-wide identification and analysis of human tissuespecific differentially methylated regions (tDMRs). Genome Research 18, 1518-1529.
75. Rosa A, Picchioni MM, Kalidindi S, Loat CS, Knight J, Toulopoulou T, Vonk R, van der Schot AC, Nolen W, Kahn RS, McGuffin P, Murray RM, Craig IW (2008). Differential methylation of the X-chromosome is a possible source of discordance for bipolar disorder female monozygotic twins. American Journal of Medical Genetics : Part B Neuropsychiatric Genetics 147B, 459-462. (Pubitemid 351830803)
76. Roth TL, Lubin FD, Funk AJ, Sweatt JD (2009). Lasting epigenetic influence of early-life adversity on the BDNF gene. Biological Psychiatry 65, 760-769.
77. Rutter M (2009). Epidemiological methods to tackle causal questions. International Journal of Epidemiology 38, 3-6.
78. Sanchez MM (2006). The impact of early adverse care on HPA axis development: Nonhuman primate models. Hormones and Behavior 50, 623-631. (Pubitemid 44307110)
79. Shakoor S, Jaffee SR, Andreou P, Bowes L, Ambler AP, Caspi A, Moffitt TE, Arseneault L (2011). Mothers and children as informants of bullying victimization : Results from an epidemiological cohort of children. Journal of Abnormal Child Psychology 39, 379-387.
80. Suomi SJ (1997). Early determinants of behaviour : Evidence from primate studies. British Medical Bulletin 53, 170-184. (Pubitemid 27129185)
81. Susman EJ (2006). Psychobiology of persistent antisocial behavior : Stress, early vulnerabilities and the attenuation hypothesis. Neuroscience and Biobehavioral Reviews 30, 376-389. (Pubitemid 43230169)
82. Talens RP, Boomsma DI, Tobi EW, Kremer D, Jukema JW, Willemsen G, Putter H, Slagboom PE, Heijmans BT (2010). Variation, patterns, and temporal stability of DNA methylation : Considerations for epigenetic epidemiology. Federation of the American Societies for Experimental Biology 24, 3135-3144.
83. Tarullo AR, Gunnar MR (2006). Child maltreatment and the developing HPA axis. Hormone and Behavior 50, 632-639. (Pubitemid 44307108)
84. Tobi EW, Lumey LH, Talens RP, Kremer D, Putter H, Stein AD, Slagboom PE, Heijmans BT (2009). DNA methylation differences after exposure to prenatal famine are common and timing-and sex-specific. Human Molecular Genetics 18, 4046-4053.
85. Tsankova N, Renthal W, Kumar A, Nestler EJ (2007). Epigenetic regulation in psychiatric disorders. Nature Reviews Neuroscience 8, 355-367. (Pubitemid 46652469)
86. Tyrka AR, Price LH, Marsit C, Walters OC, Carpenter LL (2012). Childhood adversity and epigenetic modulation of the leukocyte glucocorticoid receptor : Preliminary findings in healthy adults. PloS One 7, e30148.
87. Tyrka AR, Wier L, Price LH, Ross N, Anderson GM, Wilkinson CW, Carpenter LL (2008). Childhood parental loss and adult hypothalamic-pituitary-adrenal function. Biological Psychiatry 63, 1147-1154.
88. Uher R, McGuffin P (2010). The moderation by the serotonin transporter gene of environmental adversity in the etiology of depression : 2009 update. Molecular Psychiatry 15, 18-22.
89. van Goozen SH, Fairchild G, Snoek H, Harold GT (2007). The evidence for a neurobiological model of childhood antisocial behavior. Psychological Bulletin 133, 149-182.
90. Vazquez DM, Neal Jr. CR, Patel PD, Kaciroti N, Lopez JF (2012). Regulation of corticoid and serotonin receptor brain system following early life exposure of glucocorticoids : Long term implications for the neurobiology of mood. Psychoneuroendocrinology 37, 421-437.
91. Vielhaber K, Riemann D, Feige B, Kuelz A, Kirschbaum C, Voderholzer U (2005). Impact of experimentally induced serotonin deficiency by tryptophan depletion on saliva cortisol concentrations. Pharmacopsychiatry 38, 87-94. (Pubitemid 40388788)
92. Weaver IC, Cervoni N, Champagne FA, D'Alessio AC, Sharma S, Seckl JR, Dymov S, Szyf M, Meaney MJ (2004). Epigenetic programming by maternal behavior. Nature Neuroscience 7, 847-854. (Pubitemid 38989508)
93. Williams RL (2000). A note on robust variance estimation for cluster-correlated data. Biometrics 56, 645-646. (Pubitemid 30422662)
94. Wong CC, Caspi A, Williams B, Craig IW, Houts R, Ambler A, Moffitt TE, Mill J (2010). A longitudinal study of epigenetic variation in twins. Epigenetics 5, 516-526.
95. Yehuda R, Flory JD, Pratchett LC, Buxbaum J, Ising M, Holsboer F (2010). Putative biological mechanisms for the association between early life adversity and the subsequent development of PTSD. Psychopharmacology 212, 405-417.