The Val66Met coding variant of the brain-derived neurotrophic factor (BDNF) gene does not contribute toward variation in the personality trait neuroticism.
BACKGROUND
The val66met variant located within the brain-derived neurotrophic factor gene (BDNF) has previously been associated with human neuroticism, a dimension of personality strongly predictive of depressive illness.


METHODS
Here we report an attempt to replicate this association using three populations of extreme neuroticism scorers derived from two large English cohorts (n = 88,142 and n = 20,921). On the basis of the current literature, which indicates that an effect of BDNF may only become apparent in those individuals exposed to stress, a gene-environment interaction was also sought.


RESULTS
No statistically significant effects were identified, although simulations indicated that the samples held sufficient power to detect a main effect accounting for just .75% of variation and an interaction accounting for 4% of variation.


CONCLUSIONS
These data do not support the hypothesis that the val66met BDNF polymorphism contributes toward variation in the human personality trait neuroticism, at least as indexed by the Eysenck Personality Questionnaire.
Willis-Owen
Saffron A G
SA
Wellcome Trust Centre for Human Genetics, Oxford University, Oxford, UK. saffron.willis-owen@well.ox.ac.uk
Fullerton
Jan
J
Surtees
Paul G
PG
Wainwright
Nick W J
NW
Miller
Susette
S
Flint
Jonathan
J
D000293:Adolescent; D000328:Adult; D019943:Amino Acid Substitution; D001499:Bayes Theorem; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D002648:Child; D004644:Emotions; D005190:Family; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D008297:Male; D015233:Models, Statistical; D009497:Neurotic Disorders / Q000235:genetics* / Q000523:psychology*; D010551:Personality; D010556:Personality Tests; D011569:Psychiatric Status Rating Scales; D012189:Retrospective Studies; D012919:Social Behavior; D012931:Social Environment; D006113:United Kingdom / Q000453:epidemiology; D044465:White People
D019208:Brain-Derived Neurotrophic Factor