title: BDNF val(66)met genotype shows distinct associations with the acoustic startle reflex and the cortisol stress response in young adults and children.
abstract: Brain Derived Neurotrophic Factor (BDNF) is a crucial regulator of neuronal development, organization and function and the val(66)met polymorphism in the BDNF gene has been associated with several (endo-) phenotypes of cognitive and affective processing. The BDNF met allele is considered a risk factor for anxiety and fear related phenotypes although findings are not entirely consistent. Here, the impact of BDNF val(66)met on two parameters of anxiety and stress was investigated in a series of studies. Acoustic startle responses were assessed in three adult samples (N1=117, N2=104, N3=116) as well as a children sample (N4=123). Cortisol increase in response to the Trier Social Stress Test (TSST) was measured in one adult sample (N3) and in the children sample (N4). The BDNF met allele was associated with enhanced cortisol responses in young adults (p=0.039) and children (p=0.013). On the contrary, BDNF met allele carriers showed a reduced acoustic startle response which reached significance in most samples (N1: p=0.004; N2: p=0.045; N3: n.s., N4: p=0.043) pointing to differential effects of BDNF val(66)met on distinct endophenotypes of anxiety and stress-related responses. However, small effect sizes suggest substantial additional genetic as well as environmental contributors.
authors.affiliation: Institute of Psychology II, Technische Universität Dresden, Dresden, Germany. Electronic address: diana.armbruster@tu-dresden.de.
authors.forename: Diana
authors.initials: D
authors.lastname: Armbruster
authors.affiliation: MSH Medical School Hamburg, University of Applied Science and Medical University, Hamburg, Germany.
authors.forename: Anett
authors.initials: A
authors.lastname: Müller-Alcazar
authors.affiliation: Institute of Psychology II, Technische Universität Dresden, Dresden, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Strobel
authors.affiliation: Division of Molecular Psychiatry, Laboratory of Translational Neurobiology, Department of Psychiatry, Psychosomatics, and Psychotherapy, University of Wuerzburg, Wuerzburg, Germany.
authors.forename: Klaus-Peter
authors.initials: KP
authors.lastname: Lesch
authors.affiliation: Institute of Psychology I, Technische Universität Dresden, Dresden, Germany.
authors.forename: Clemens
authors.initials: C
authors.lastname: Kirschbaum
authors.affiliation: Institute of Psychology II, Technische Universität Dresden, Dresden, Germany.
authors.forename: Burkhard
authors.initials: B
authors.lastname: Brocke
mesh_terms: D000161:Acoustic Stimulation; D000293:Adolescent; D000328:Adult; D019943:Amino Acid Substitution / Q000235:genetics; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D002648:Child; D005260:Female; D056726:Genetic Association Studies; D005838:Genotype; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008297:Male; D008715:Methionine / Q000235:genetics; D013216:Reflex, Startle; D013315:Stress, Psychological / Q000235:genetics* / Q000378:metabolism; D014633:Valine / Q000235:genetics; D055815:Young Adult
chemical_list: D019208:Brain-Derived Neurotrophic Factor; C579455:BDNF protein, human; D008715:Methionine; D014633:Valine; D006854:Hydrocortisone
keywords: Acoustic startle response; BDNF val(66)met; Cortisol stress reponse; Negative emotionality; TSST