INTRODUCTION: Variance in hypothalamic-pituitary-adrenal (HPA) axis reactivity is considered to be one of the sources of differences in infant temperament. The cortisol enters into interactions with dopamine and serotonin, so it is expected that polymorphisms in genes coding monoamine metabolism influence both HPA axis reactivity and temperament. METHODS: We therefore explore the relationship among 5-HTTLPR S/L, MAOA H/L, and COMT Val158Met polymorphisms, the stress reaction of newborn infants after a heel stick blood draw (measured by determining salivary cortisol at three time points), and temperament assessed at the age of 3 months using Rothbart's Infant Behavior Questionnaire-Revised (IBQ-R) with a sample of 84 infants. RESULTS: The decrease in the salivary cortisol correlated with nine primary scales and all three secondary scales of IBQ-R. Children with a greater cortisol decrease were assessed as less susceptible to negative emotions, more extraverted, and more regulated. The polymorphisms that were observed were related both to the course of the stress reaction and to temperament. The 5-HTTLPR S allele was connected to higher scores for Negative Emotionality and lower scores for Orienting/Regulatory Capacity. The presence of the MAOA L allele predisposed its carriers to higher scores for Negative Emotionality, lower scores for Orienting/Regulatory Capacity, and a lower decrease in cortisol. The Met allele of COMT Val158Met polymorphism was connected to a higher Positive Affectivity/Surgency and Orienting/Regulatory Capacity and a greater cortisol decrease. CONCLUSIONS: Contrary to previous studies referring mainly basal cortisol and its increase, the results of our study emphasize the importance of cortisol elimination in infant temperament. Another interesting finding was a higher cortisol increase, higher Distress to Limitations, Negative Emotionality, and Approach in MAOA LL homozygotes which are traditionally understood as more vulnerable toward early stress in developing later externalizing behavior.

Department of Molecular Biology and Genetics Faculty of Science University of South Bohemia Ceske Budejovice Czech Republic

Department of Pedagogy and Psychology Faculty of Education University of South Bohemia Ceske Budejovice Czech Republic

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Auerbach, J. G. , Faroy, M. , Ebstein, R. , Kahana, M. , & Levine, J. (2001). The association of the dopamine D4 receptor gene (DRD4) and the serotonin transporter promoter gene (5‐HTTLPR) with temperament in 12‐month‐old infants. Journal of Child Psychology and Psychiatry, 42, 777–783. 10.1017/S0021963001007612 PubMed DOI

Auerbach, J. , Geller, V. , Lezer, S. , Shinwell, E. , Belmaker, R. H. , Levine, J. , & Ebstein, R. P. (1999). Dopamine D4 receptor (D4DR) and serotonin transporter promoter (5‐HTTLPR) polymorphisms in the determination of temperament in 2‐month‐old infants. Molecular Psychiatry, 4, 369–373. 10.1038/sj.mp.4000531 PubMed DOI

Barnett, J. H. , Jones, P. B. , Robbins, T. W. , & Müller, U. (2007). Effects of the catechol‐O‐methyltransferase Val158Met polymorphism on executive function: A meta‐analysis of the Wisconsin Card Sort Test in schizophrenia and healthy controls. Molecular Psychiatry, 12, 502–509. 10.1038/sj.mp.4001973 PubMed DOI

Baron, R. M. , & Kenny, D. A. (1986). The moderator–mediator variable distinction in social psychological research: Conceptual, strategic, and statistical considerations. Journal of Personality and Social Psychology, 51, 1173–1182. 10.1037//0022-3514.51.6.1173 PubMed DOI

Beijers, R. , Riksen‐Walraven, M. , & de Weerth, C. (2012). Cortisol regulation in 12‐month‐olds: Associations with the infants’ early history of breastfeeding and co‐sleeping In Beijers R. (Ed.), The early maternal and caregiving environment: Longitudinal links with infant regulation and health (Doctoral dissertation) (pp. 75–106). Nijmegen: Radboud University; Retrieved from: https://repository.ubn.ru.nl/bitstream/handle/2066/98576/98576.pdf?sequence=1#page=76

Bellgrove, M. A. , Domschke, K. , Hawi, Z. , Kirley, A. , Mullins, C. , Robertson, I. H. , & Gill, M. (2005). The methionine allele of the COMT polymorphism impairs prefrontal cognition in children and adolescents with ADHD. Experimental Brain Research, 163, 352–360. 10.1007/s00221-004-2180-y PubMed DOI

Bishop, S. J. , Cohen, J. D. , Fossella, J. , Casey, B. J. , & Farah, M. J. (2006). COMT genotype influences prefrontal response to emotional distraction. Cognitive, Affective, & Behavioral Neuroscience, 6(1), 62–70. 10.3758/CABN.6.1.62 PubMed DOI

Blair, C. , Granger, D. A. , Kivlighan, K. T. , Mills‐Koonce, R. , Willoughby, M. , Greenberg, M. T. , … Fortunato, C. K. (2008). Maternal and child contributions to cortisol response to emotional arousal in young children from low‐income, rural communities. Developmental Psychology, 44, 1095–1109. 10.1037/0012-1649.44.4.1095 PubMed DOI

Blair, C. , Granger, D. A. , Willoughby, M. , Mills‐Koonce, R. , Cox, M. , Greenberg, M. T. , … Investigators, F. L. P. (2011). Salivary cortisol mediates effects of poverty and parenting on executive functions in early childhood. Child Development, 82, 1970–1984. 10.1111/j.1467-8624.2011.01643.x PubMed DOI PMC

Blair, C. , Peters, R. , & Granger, D. (2004). Physiological and neuropsychological correlates of approach/withdrawal tendencies in preschool: Further examination of the behavioral inhibition system/behavioral activation system scales for young children. Developmental Psychobiology, 45(3), 113–124. 10.1002/dev.20022 PubMed DOI

Bornstein, S. R. , Schuppenies, A. , Wong, M. L. , & Licinio, J. (2006). Approaching the shared biology of obesity and depression: The stress axis as the locus of gene–environment interactions. Molecular Psychiatry, 11, 892–902. 10.1038/sj.mp.4001873 PubMed DOI

Bouma, E. M. C. , Riese, H. , Doornbos, B. , Ormel, J. , & Oldehinkel, A. J. (2012). Genetically based reduced MAOA and COMT functioning is associated with the cortisol stress response: A replication study. Molecular Psychiatry, 17, 119–121. 10.1038/mp.2011.115 PubMed DOI

Bruder, G. E. , Keilp, J. G. , Xu, H. , Shikhman, M. , Schori, E. , Gorman, J. M. , & Gilliam, T. C. (2005). Catechol‐O‐methyltransferase (COMT) genotypes and working memory: Associations with differing cognitive operations. Biological Psychiatry, 58, 901–907. 10.1016/j.biopsych.2005.05.010 PubMed DOI

Brummett, B. H. , Boyle, S. H. , Siegler, I. C. , Kuhn, C. M. , Surwit, R. S. , Garrett, M. E. , … Williams, R. B. (2008). HPA axis function in male caregivers: Effect of the monoamine oxidase‐A gene promoter (MAOA‐uVNTR). Biological Psychology, 79, 250–255. 10.1016/j.biopsycho.2008.06.004 PubMed DOI PMC

Caspi, A. , McClay, J. , Moffitt, T. E. , Mill, J. , Martin, J. , Craig, I. W. , … Poulton, R. (2002). Role of genotype in the cycle of violence in maltreated children. Science, 297, 851–854. 10.1126/science.1072290 PubMed DOI

Caspi, A. , Sugden, K. , Moffitt, T. E. , Taylor, A. , Craig, I. W. , Harrington, H. , … Poulton, R. (2003). Influence of life stress on depression: Moderation by a polymorphism in the 5‐HTT gene. Science, 301, 386–389. 10.1126/science.1083968 PubMed DOI

Cassano, W. J. Jr , & D’mello, A. P. (2001). Acute stress-induced facilitation of the hypothalamic‐pituitary-adrenal axis: evidence for the roles of stressor duration and serotonin. Neuroendocrinology, 74(3), 167–177. 10.1159/000054683 PubMed DOI

Chen, J. , Lipska, B. K. , Halim, N. , Ma, Q. D. , Matsumoto, M. , Melhem, S. , … Weinberger, D. R. (2004). Functional analysis of genetic variation in catechol‐O‐methyltransferase (COMT): Effects on mRNA, protein, and enzyme activity in postmortem human brain. The American Journal of Human Genetics, 75, 807–821. 10.1086/425589 PubMed DOI PMC

Davis, E. P. , Donzella, B. , Krueger, W. K. , & Gunnar, M. R. (1999). The start of a new school year: Individual differences in salivary cortisol response in relation to child temperament. Developmental Psychobiology: The Journal of the International Society for Developmental Psychobiology, 35(3), 188–196. 10.1002/(SICI)1098-2302(199911)35:3<188:AID-DEV3>3.0.CO;2-K PubMed DOI

Dettling, A. C. , Gunnar, M. R. , & Donzella, B. (1999). Cortisol levels of young children in full‐day childcare centers: Relations with age and temperament. Psychoneuroendocrinology, 24, 519–536. 10.1016/S0306-4530(99)00009-8 PubMed DOI

Effect sizes calculator for non‐parametric tests: Mann‐Whitney‐U, Wilcoxon‐W and Kruskall‐Wallis‐H [software].

Eisenberger, N. I. , Way, B. M. , Taylor, S. E. , Welch, W. T. , & Lieberman, M. D. (2007). Understanding genetic risk for aggression: Clues from the brain’s response to social exclusion. Biological Psychiatry, 61, 1100–1108. 10.1016/j.biopsych.2006.08.007 PubMed DOI

Eisenberg, J. C. , Mei‐Tal, G. , Steinberg, A. , Tartakovsky, E. , Zohar, A.. , Gritsenko, I. , … Ebstein, R. P. (1999). Haplotype relative risk study of catechol‐O‐methyltransferase (COMT) and attention deficit hyperactivity disorder (ADHD): Association of the high‐enzyme activity val allele with adhd impulsivehyperactive phenotype. American journal of Medical Genetics, 88(5), 497–502. 10.1002/(SICI)1096-8628(19991015)88:5<497::AID-AJMG12>3.0.CO;2-F PubMed DOI

Eley, T. C. , Sugden, K. , Corsico, A. , Gregory, A. M. , Sham, P. , McGuffin, P. , … Craig, I. W. (2004). Gene–environment interaction analysis of serotonin system markers with adolescent depression. Molecular Psychiatry, 9, 908–915. 10.1038/sj.mp.4001546 PubMed DOI

Frazzetto, G. , Di Lorenzo, G. , Carola, V. , Proietti, L. , Sokolowska, E. , Siracusano, A. , … Troisi, A. (2007). Early trauma and increased risk for physical aggression during adulthood: The moderating role of MAOA genotype. PLoS ONE, 2(5), e486 10.1371/journal.pone.0000486 PubMed DOI PMC

Gartstein, M. A. , & Rothbart, M. K. (2003). Studying infant temperament via the Revised Infant Behavior Questionnaire. Infant Behavior and Development., 26, 64–86. 10.1016/S0163-6383(02)00169-8 DOI

Gibb, B. E. , Uhrlass, D. J. , Grassia, M. , Benas, J. S. , & McGeary, J. (2009). Children’s inferential styles, 5‐HTTLPR genotype, and maternal expressed emotion‐criticism: An integrated model for the intergenerational transmission of depression. Journal of Abnormal Psychology, 118(4), 734 10.1037/a0016765 PubMed DOI PMC

Goldsmith, H. H. , Buss, A. H. , Plomin, R. , Rothbart, M. K. , Thomas, A. , Chess, S. , … McCall, R. B. (1987). Roundtable: What is temperament? Four approaches. Child Development, 58, 505–529. 10.2307/1130527 PubMed DOI

Gottlieb, G. , & Halpern, C. T. (2002). A relational view of causality in normal and abnormal development. Development and Psychopathology, 14(3), 421–435. 10.1017/S0954579402003024 PubMed DOI

Greenberg, B. D. , Tolliver, T. J. , Huang, S. J. , Li, Q. , Bengel, D. , & Murphy, D. L. (1999). Genetic variation in the serotonin transporter promoter region affects serotonin uptake in human blood platelets. American Journal of Medical Genetics, 88(1), 83–87. 10.1002/(SICI)1096-8628(19990205)88:1 PubMed DOI

Grossmann, T. , Johnson, M. H. , Vaish, A. , Hughes, D. A. , Quinque, D. , Stoneking, M. , & Friederici, A. D. (2011). Genetic and neural dissociation of individual responses to emotional expressions in human infants. Developmental Cognitive Neuroscience, 1(1), 57–66. 10.1016/j.dcn.2010.07.001 PubMed DOI PMC

Gunnar, M. R. (1994). Psychoendocrine studies of temperament and stress in early childhood: Expanding current models In Bates J. E., & Wachs T. D. (Eds.), Temperament: Individual differences at the interface of biology and behavior. Washington, DC: American psychological Association.

Gunnar, M. R. , Doom, J. R. , & Esposito, E. A. (2015). Psychoneuroendocrinology of stress: Normative development and individual differences In Lerner R.M. (Ed), Handbook of Child Psychology and Developmental Science (pp. 106–151). Florida: John Wiley & Sons.

Gunnar, M. R. , Larson, M. C. , Hertsgaard, L. , Harris, M. L. , & Brodersen, L. (1992). The stressfulness of separation among nine‐month‐old infants: Effects of social context variables and infant temperament. Child Development, 63, 290–303. 10.1111/j.1467-8624.1992.tb01627.x PubMed DOI

Gunnar, M. R. , Porter, F. L. , Wolf, C. M. , Rigatuso, J. , & Larson, M. C. (1995). Neonatal stress reactivity: Predictions to later emotional temperament. Child Development, 66, 1–13. 10.1111/j.1467-8624.1995.tb00851.x PubMed DOI

Gunnar, M. R. , Tout, K. , de Haan, M. , Pierce, S. , & Stansbury, K. (1997). Temperament, social competence, and adrenocortical activity in preschoolers. Developmental Psychobiology, 31(1), 65–85. 10.1002/(SICI)1098-2302(199707)31:1 PubMed DOI

Hill, J. , Breen, G. , Quinn, J. , Tibu, F. , Sharp, H. , & Pickles, A. (2013). Evidence for interplay between genes and maternal stress in utero: Monoamine oxidase A polymorphism moderates effects of life events during pregnancy on infant negative emotionality at 5 weeks. Genes, Brain and Behavior, 12, 388–396. 10.1111/gbb.12033 PubMed DOI

Holmboe, K. , Nemoda, Z. , Fearon, R. M. , Csibra, G. , Sasvari‐Szekely, M. , & Johnson, M. H. (2010). Polymorphisms in dopamine system genes are associated with individual differences in attention in infancy. Developmental Psychology, 46, 404–416. 10.1037/a0018180 PubMed DOI PMC

Huisman, M. (2000). Imputation of missing item responses: Some simple techniques. Quality and Quantity, 34, 331–351. 10.1023/A:1004782230065 DOI

Jabbi, M. , Korf, J. , Kema, I. P. , Hartman, C. , Van der Pompe, G. , Minderaa, R. B. , … Den Boer, J. A. (2007). Convergent genetic modulation of the endocrine stress response involves polymorphic variations of 5‐HTT, COMT and MAOA. Molecular Psychiatry, 12, 483–490. 10.1038/sj.mp.4001975 PubMed DOI

Jensen, K. B. , Lonsdorf, T. B. , Schalling, M. , Kosek, E. , & Ingvar, M. (2009). Increased sensitivity to thermal pain following a single opiate dose is influenced by the COMT val 158 met polymorphism. PLoS ONE, 4(6), e6016 10.1371/journal.pone.0006016 PubMed DOI PMC

Kagan, J. , Reznick, J. S. , & Snidman, N. (1987). The physiology and psychology of behavioral inhibition in children. Child Development, 58, 1459–1473. 10.2307/1130685 PubMed DOI

Kendler, K. S. , Kuhn, J. W. , Vittum, J. , Prescott, C. A. , & Riley, B. (2005). The interaction of stressful life events and a serotonin transporter polymorphism in the prediction of episodes of major depression: A replication. Archives of General Psychiatry, 62, 529–535. 10.1001/archpsyc.62.5.529 PubMed DOI

Kiff, C. J. , Lengua, L. J. , & Zalewski, M. (2011). Nature and nurturing: Parenting in the context of child temperament. Clinical Child and Family Psychology Review, 14, 251–301. 10.1007/s10567-011-0093-4 PubMed DOI PMC

Kim‐Cohen, J. , Caspi, A. , Taylor, A. , Williams, B. , Newcombe, R. , Craig, I. W. , & Moffitt, T. E. (2006). MAOA, maltreatment, and gene–environment interaction predicting children's mental health: New evidence and a meta‐analysis. Molecular Psychiatry, 11, 903–913. 10.1038/sj.mp.4001851 PubMed DOI

Kirschbaum, C. , & Hellhammer, D. H. (1994). Salivary cortisol in psychoneuroendocrine research: Recent developments and applications. Psychoneuroendocrinology, 19, 313–333. 10.1016/0306-4530(94)90013-2 PubMed DOI

Kontoangelos, K. , Papageorgiou, C. C. , Raptis, A. E. , Tsiotra, P. , Lambadiari, V. , Papadimitriou, G. N. , … Raptis, S. A. (2015). Homocysteine, cortisol, diabetes mellitus, and psychopathology. Journal of Diabetes Research, 2015, 1–10. 10.1155/2015/354923 PubMed DOI PMC

Kreek, M. J. , Nielsen, D. A. , Butelman, E. R. , & LaForge, K. S. (2005). Genetic influences on impulsivity, risk taking, stress responsivity and vulnerability to drug abuse and addiction. Nature Neuroscience, 8, 1450–1457. 10.1038/nn1583 PubMed DOI

Lachman, H. M. , Papolos, D. F. , Saito, T. , Yu, Y. M. , Szumlanski, C. L. , & Weinshilboum, R. M. (1996). Human catechol‐O‐methyltransferase pharmacogenetics: Description of a functional polymorphism and its potential application to neuropsychiatric disorders. Pharmacogenetics and Genomics, 6, 243–250. 10.1097/00008571-199606000-00007 PubMed DOI

Lajin, B. , & Alachkar, A. (2011). Detection of catechol‐O‐methyltransferase (COMT) Val158Met polymorphism by a new optimized PCR‐RFLP method. American Journal of Biomedical Science, 3(3), 170–175. 10.5099/aj110300170 DOI

Lewis, M. , & Ramsay, D. S. (1995). Developmental change in infants' responses to stress. Child Development, 66, 657–670. 10.1111/j.1467-8624.1995.tb00896.x PubMed DOI

Lowry, C. A. (2002). Functional subsets of serotonergic neurones: implications for control of the hypothalamic-pituitary-adrenal axis. Journal of Neuroendocrinology, 14(11), 911–923. 10.1046/j.1365-2826.2002.00861.x PubMed DOI

Manuck, S. B. , Flory, J. D. , Ferrell, R. E. , Mann, J. J. , & Muldoon, M. F. (2000). A regulatory polymorphism of the monoamine oxidase‐A gene may be associated with variability in aggression, impulsivity, and central nervous system serotonergic responsivity. Psychiatry Research, 95(1), 9–23. 10.1016/S0165-1781(00)00162-1 PubMed DOI

Markant, J. , Cicchetti, D. , Hetzel, S. , & Thomas, K. M. (2014). Contributions of COMT Val158Met to cognitive stability and flexibility in infancy. Developmental Science, 17, 396–411. 10.1111/desc.12128 PubMed DOI PMC

McDermott, R. , Tingley, D. , Cowden, J. , Frazzetto, G. , & Johnson, D. D. (2009). Monoamine oxidase A gene (MAOA) predicts behavioral aggression following provocation. Proceedings of the National Academy of Sciences, 106, 2118–2123. 10.1073/pnas.0808376106 PubMed DOI PMC

Miller, R. , Wankerl, M. , Stalder, T. , Kirschbaum, C. , & Alexander, N. (2013). The serotonin transporter gene‐linked polymorphic region (5‐HTTLPR) and cortisol stress reactivity: A meta‐analysis. Molecular Psychiatry, 18, 1018–1024. 10.1038/mp.2012.124 PubMed DOI

Morris, M. C. , Compas, B. E. , & Garber, J. (2012). Relations among posttraumatic stress disorder, comorbid major depression, and HPA function: A systematic review and meta‐analysis. Clinical Psychology Review, 32, 301–315. 10.1016/j.cpr.2012.02.002 PubMed DOI PMC

Mueller, A. , Brocke, B. , Fries, E. , Lesch, K. P. , & Kirschbaum, C. (2010). The role of the serotonin transporter polymorphism for the endocrine stress response in newborns. Psychoneuroendocrinology, 35, 289–296. 10.1016/j.psyneuen.2009.07.002 PubMed DOI

Pagliaccio, D. , Luby, J. L. , Bogdan, R. , Agrawal, A. , Gaffrey, M. S. , Belden, A. C. , … Barch, D. M. (2014). Stress‐system genes and life stress predict cortisol levels and amygdala and hippocampal volumes in children. Neuropsychopharmacology, 39, 1245–1253. 10.1038/npp.2013.327 PubMed DOI PMC

Paloyelis, Y. , Asherson, P. , Mehta, M. A. , Faraone, S. V. , & Kuntsi, J. (2010). DAT1 and COMT effects on delay discounting and trait impulsivity in male adolescents with attention deficit/hyperactivity disorder and healthy controls. Neuropsychopharmacology, 35, 2414–2426. 10.1038/npp.2010.124 PubMed DOI PMC

Pariante, C. M. , & Lightman, S. L. (2008). The HPA axis in major depression: Classical theories and new developments. Trends in Neurosciences, 31, 464–468. 10.1016/j.tins.2008.06.006 PubMed DOI

Pérez‐Edgar, K. , Schmidt, L. A. , Henderson, H. A. , Schulkin, J. , & Fox, N. A. (2008). Salivary cortisol levels and infant temperament shape developmental trajectories in boys at risk for behavioral maladjustment. Psychoneuroendocrinology, 33, 916–925. 10.1016/j.psyneuen.2008.03.018 PubMed DOI PMC

Pluess, M. , Velders, F. P. , Belsky, J. , van IJzendoorn, M. H. , Bakermans‐Kranenburg, M. J. , Jaddoe, V. W. V. , … Tiemeier, H. (2011). Serotonin transporter polymorphism moderates effects of prenatal maternal anxiety on infant negative emotionality. Biological Psychiatry, 69, 520–525. 10.1016/j.biopsych.2010.10.006 PubMed DOI

Praschak‐Rieder, N. , Kennedy, J. , Wilson, A. A. , Hussey, D. , Boovariwala, A. , Willeit, M. , … Meyer, J. H. (2007). Novel 5‐HTTLPR allele associates with higher serotonin transporter binding in putamen: A [11 C] DASB positron emission tomography study. Biological Psychiatry, 62, 327–331. 10.1016/j.biopsych.2006.09.022 PubMed DOI

Preacher, K. J. , & Leonardelli, G. J. . (n.d.). Calculation for the Sobel test: An interactive calculation tool for mediation tests. (software). Retrieved from: http://quantpsy.org/sobel/sobel.htm.

Rothbart, M. K. (1981). Development of individual differences in temperament. Advances in Developmental Psychology, 1, 37–86.

Rothbart, M. K. , & Derryberry, D. (1981). Development of individual differences in temperament In Lamb M. E., & Brown A. L. (Eds.), Advances in developmental psychology, Vol. 1 (pp. 37–86). Hillsdale, NJ: Erlbaum.

Sabol, S. Z. , Hu, S. , & Hamer, D. (1998). A functional polymorphism in the monoamine oxidase A gene promoter. Human Genetics, 103, 273–279. 10.1007/s004390050816 PubMed DOI

Santiago, L. B. , Jorge, S. M. , & Moreira, A. C. (1996). Longitudinal evaluation of the development of salivary cortisol circadian rhythm in infancy. Clinical Endocrinology, 44, 157–161. 10.1046/j.1365-2265.1996.645466.x PubMed DOI

Sapolsky, R. M. , Romero, L. M. , & Munck, A. U. (2000). How do glucocorticoids influence stress responses? Integrating permissive, suppressive, stimulatory, and preparative actions. Endocrine Reviews, 21(1), 55–89. PubMed

Schinka, J. A. , Busch, R. M. , & Robichaux‐Keene, N. (2004). A meta‐analysis of the association between the serotonin transporter gene polymorphism (5‐HTTLPR) and trait anxiety. Molecular Psychiatry, 9, 197–202. 10.1038/sj.mp.4001405 PubMed DOI

Sen, S. , Burmeister, M. , & Ghosh, D. (2004). Meta‐analysis of the association between a serotonin transporter promoter polymorphism (5‐HTTLPR) and anxiety‐related personality traits. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics, 127(1), 85–89. 10.1002/ajmg.b.20158 PubMed DOI

Sheese, B. E. , Voelker, P. , Posner, M. I. , & Rothbart, M. K. (2009). Genetic variation influences on the early development of reactive emotions and their regulation by attention. Cognitive Neuropsychiatry, 14, 332–355. 10.1080/13546800902844064 PubMed DOI

Smider, N. A. , Essex, M. J. , Kalin, N. H. , Buss, K. A. , Klein, M. H. , Davidson, R. J. , & Goldsmith, H. H. (2002). Salivary cortisol as a predictor of socioemotional adjustment during kindergarten: A prospective study. Child Development, 73, 75–92. 10.1111/1467-8624.00393 PubMed DOI

Smith, A. K. , White, P. D. , Aslakson, E. , Vollmer‐Conna, U. , & Rajeevan, M. S. (2006). Polymorphisms in genes regulating the HPA axis associated with empirically delineated classes of unexplained chronic fatigue. Pharmacogenomics, 7, 387–394. 10.2217/14622416.7.3.387 PubMed DOI

Smolka, M. N. , Bühler, M. , Schumann, G. , Klein, S. , Hu, X. Z. , Moayer, M. , … Heinz, A. (2007). Gene–gene effects on central processing of aversive stimuli. Molecular Psychiatry, 12, 307–317. 10.1038/sj.mp.4001946 PubMed DOI

Sullivan, R. M. , & Dufresne, M. M. (2006). Mesocortical dopamine and HPA axis regulation: Role of laterality and early environment. Brain Research, 1076(1), 49–59. 10.1016/j.brainres.2005.12.100 PubMed DOI

Talge, N. M. , Donzella, B. , & Gunnar, M. R. (2008). Fearful temperament and stress reactivity among preschool‐aged children. Infant and Child Development, 17, 427–445. 10.1002/icd.585 PubMed DOI PMC

Turner‐Cobb, J. M. , Rixon, L. , & Jessop, D. S. (2008). A prospective study of diurnal cortisol responses to the social experience of school transition in four‐year‐old children: Anticipation, exposure, and adaptation. Developmental Psychobiology: The Journal of the International Society for Developmental Psychobiology, 50(4), 377–389. 10.1002/dev.20298 PubMed DOI

Tyrka, A. R. , Wier, L. , Price, L. H. , Ross, N. , Anderson, G. M. , Wilkinson, C. W. , & Carpenter, L. L. (2008). Childhood parental loss and adult hypothalamic‐pituitary‐adrenal function. Biological Psychiatry, 63(12), 1147–1154. 10.1016/j.biopsych.2008.01.011 PubMed DOI PMC

Van Bakel, H. J. , & Riksen‐Walraven, J. M. (2004). Stress reactivity in 15‐month‐old infants: Links with infant temperament, cognitive competence, and attachment security. Developmental Psychobiology, 44, 157–167. 10.1002/dev.20001 PubMed DOI

Van den Bergh, B. R. , Van Calster, B. , Smits, T. , Van Huffel, S. , & Lagae, L. (2008). Antenatal maternal anxiety is related to HPA‐axis dysregulation and self‐reported depressive symptoms in adolescence: A prospective study on the fetal origins of depressed mood. Neuropsychopharmacology, 33, 536–545. 10.1111/1467-8624.00583 PubMed DOI

Wagner, S. , Baskaya, Ö. , Anicker, N. J. , Dahmen, N. , Lieb, K. , & Tadić, A. (2010). The catechol o‐methyltransferase (COMT) val158met polymorphism modulates the association of serious life events (SLE) and impulsive aggression in female patients with borderline personality disorder (BPD). Acta Psychiatrica Scandinavica, 122(2), 110–117. 10.1111/j.1600-0447.2009.01501.x PubMed DOI

Watamura, S. E. , Donzella, B. , Alwin, J. , & Gunnar, M. R. (2003). Morning‐to‐afternoon increases in cortisol concentrations for infants and toddlers at child care: Age differences and behavioral correlates. Child Development, 74, 1006–1020. 10.1111/1467-8624.00583 PubMed DOI

Wendland, J. R. , Martin, B. J. , Kruse, M. R. , Lesch, K. P. , & Murphy, D. L. (2006). Simultaneous genotyping of four functional loci of human SLC6A4, with a reappraisal of 5‐HTTLPR and rs25531. Molecular Psychiatry, 11, 224–224. 10.1038/sj.mp.4001789 PubMed DOI

White, B. P. , Gunnar, M. R. , Larson, M. C. , Donzella, B. , & Barr, R. G. (2000). Behavioral and physiological responsivity, sleep, and patterns of daily cortisol production in infants with and without colic. Child Development, 71, 862–877. 10.1111/1467-8624.00196 PubMed DOI

Wichers, M. , Aguilera, M. , Kenis, G. , Krabbendam, L. , Myin‐Germeys, I. , Jacobs, N. , … van Os, J. (2008). The catechol‐O‐methyl transferase Val158Met polymorphism and experience of reward in the flow of daily life. Neuropsychopharmacology, 33, 3030–3036. 10.1038/sj.npp.1301520 PubMed DOI

Yavich, L. , Forsberg, M. M. , Karayiorgou, M. , Gogos, J. A. , & Männistö, P. T. (2007). Site‐specific role of catechol‐O‐methyltransferase in dopamine overflow within prefrontal cortex and dorsal striatum. Journal of Neuroscience, 27, 10196–10209. 10.1523/JNEUROSCI.0665-07.2007 PubMed DOI PMC

Yehuda, R. , Flory, J. D. , Pratchett, L. C. , Buxbaum, J. , Ising, M. , & Holsboer, F. (2010). Putative biological mechanisms for the association between early life adversity and the subsequent development of PTSD. Psychopharmacology (Berl), 212, 405–417. 10.1007/s00213-010-1969-6 PubMed DOI

Younger, W. Y. , Tsai, S. J. , Hong, C. J. , Chen, T. J. , Chen, M. C. , & Yang, C. W. (2005). Association study of a monoamine oxidase a gene promoter polymorphism with major depressive disorder and antidepressant response. Neuropsychopharmacology, 30, 1719–1723. PubMed

Zhang, M. , Chen, X. , Way, N. , Yoshikawa, H. , Deng, H. , Ke, X. , … Lu, Z. (2011). The association between infants’ self‐regulatory behavior and MAOA gene polymorphism. Developmental Science, 14, 1059–1065. 10.1111/j.1467-7687.2011.01047.x PubMed DOI