Early impact of 5-HTTLPR polymorphism on the neural correlates of sadness.
Healthy adults carrying the short (S) allele of the human serotonin transporter gene linked polymorphism (5-HTTLPR) show increased amygdala activation during visual processing of emotionally negative stimuli compared to healthy adults homozygous for the long (L) allele. To determine whether abnormal brain responses during negative emotion appear early in life in S allele carriers, functional magnetic resonance imaging (fMRI) was used to measure brain activity during a transient state of sadness in children carrying the S allele (S group) or homozygous for the L allele (L group). Blood-oxygen-level dependent (BOLD) signal changes were measured while subjects viewed blocks of neutral film excerpts and sad film excerpts. During the sad condition (relative to the neutral condition), there was significantly greater activation in the S group compared to the L group in brain regions known to be involved in normal sadness and major depression. Given that the 5-HTTLPR polymorphism has been associated with mood disorders, it is plausible that the abnormal pattern of regional brain activity detected here, in children carrying the S allele, increases susceptibility to emotional dysregulation and depressive symptoms.
Fortier
Emilie
E
Centre de Recherche en Neuropsychologie et Cognition (CERNEC), Département de Psychologie, Université de Montréal, Montreal, Canada.
Noreau
Anne
A
Lepore
Franco
F
Boivin
Michel
M
Pérusse
Daniel
D
Rouleau
Guy A
GA
Beauregard
Mario
M
D000483:Alleles; D001931:Brain Mapping; D002648:Child; D003627:Data Interpretation, Statistical; D039721:Diagnostic and Statistical Manual of Mental Disorders; D017352:Echo-Planar Imaging; D004644:Emotions / Q000502:physiology*; D005260:Female; D005838:Genotype; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010100:Oxygen / Q000097:blood; D011110:Polymorphism, Genetic / Q000235:genetics / Q000502:physiology; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D013238:Stereotaxic Techniques
C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D010100:Oxygen