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The BDNF Val66Met polymorphism moderates the relationship between Posttraumatic Stress Disorder and fear extinction learning


Felmingham, KL and Zuj, DV and Hsu, KCM and Nicholson, E and Palmer, MA and Stuart, K and Vickers, JC and Malhi, GS and Bryant, RA, The BDNF Val66Met polymorphism moderates the relationship between Posttraumatic Stress Disorder and fear extinction learning, Psychoneuroendocrinology, 91 pp. 142-148. ISSN 0306-4530 (2018) [Refereed Article]

Copyright Statement

Copyright 2018 Elsevier Ltd.

DOI: doi:10.1016/j.psyneuen.2018.03.002


The low expression Met allele of the BDNF Val66Met polymorphism is associated with impaired fear extinction in healthy controls, and poorer response to exposure therapy in patients with Posttraumatic Stress Disorder (PTSD). Given that fear extinction underlies exposure therapy, this raises the question of the impact of BDNFVal66Met polymorphism on fear extinction in PTSD, yet this question has not yet been examined. One hundred and six participants (22 PTSD, 46 trauma-exposed controls (TC) and 38 non-trauma exposed controls (NTC)) completed a fear conditioning and extinction task and saliva samples were taken for DNA extraction and genotyped for the BDNF Val66Met polymorphism. Moderation analyses using PROCESS examined whether BDNF genotype (Val–Val vs Met carriers) moderated the relationship between PTSD symptom severity (and diagnostic status) and skin conductance response (SCR) amplitude during fear extinction. The PTSD group displayed significantly slower fear extinction learning compared to TC and NTC in the early extinction phase. The BDNF Val66Met polymorphism moderated the relationship between PTSD and fear extinction learning, such that poorer fear extinction learning was associated with greater PTSD symptom severity (and PTSD diagnostic status) in individuals with the low-expression Met allele, but no relationship was demonstrated in individuals with the Val–Val allele. This study reveals that impaired fear extinction learning is particularly evident in individuals with PTSD who carry the low-expression BDNF Met Val–Val allele and importantly not in those with the allele. This provides novel evidence of a link between BDNF and impaired fear extinction learning in PTSD, which may contribute to poorer response to exposure therapy.

Item Details

Item Type:Refereed Article
Keywords:BDNF, fear extinction, PTSD, Posttraumatic Stress Disorder, brain derived neurotrophic factor
Research Division:Psychology
Research Group:Biological psychology
Research Field:Behavioural neuroscience
Objective Division:Expanding Knowledge
Objective Group:Expanding knowledge
Objective Field:Expanding knowledge in psychology
UTAS Author:Felmingham, KL (Professor Kim Felmingham)
UTAS Author:Zuj, DV (Dr Daniel Zuj)
UTAS Author:Hsu, KCM (Mr Ken Hsu)
UTAS Author:Nicholson, E (Ms Emma Nicholson)
UTAS Author:Palmer, MA (Associate Professor Matt Palmer)
UTAS Author:Stuart, K (Miss Kimberley Stuart)
UTAS Author:Vickers, JC (Professor James Vickers)
ID Code:130902
Year Published:2018
Web of Science® Times Cited:24
Deposited By:Wicking Dementia Research and Education Centre
Deposited On:2019-02-20
Last Modified:2019-04-01

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