5-HTTLPR genotype influences amygdala volume.
BACKGROUND
Functional imaging studies in healthy individuals revealed an association between 5-HTTLPR genotype and neuronal activity in the amygdala. The aim of this study was firstly to investigate a possible overall impact of the 5-HTTLPR on amygdala volume in patients with bipolar disorder and healthy individuals and secondly to test a diagnosis specific influence of the 5-HTTLPR on amygdala volume.


METHODS
We performed a region of interest analysis of amygdala volume in 37 patients with bipolar I disorder and 37 healthy control subjects. The 5-HTTLPR genotype of each proband was determined and the subjects were separated according to 5-HTTLPR genotype and for statistical analyses the groups SS and SL were combined and compared with the group LL.


RESULTS
This study shows that carriers of the short allele (SL or SS) of the 5-HTTLPR polymorphism exhibit a relatively increased volume of the right amygdala compared to homozygous L-allele carriers irrespective of diagnosis status. However, further analyses with the factors genotype and diagnosis were not able to reproduce this result.


CONCLUSIONS
The present findings are consistent with the view that the 5-HTTLPR polymorphism might modulate neuronal size or number in the amygdala. It would be worthwhile investigating the relationship between serotonin transporter function and amygdala function and volume in further studies.
Scherk
Harald
H
AMEOS Klinikum Osnabrück, Knollstr. 31, 49088, Osnabrück, Germany. hsch.gf@osnabrueck.ameos.de
Gruber
Oliver
O
Menzel
Patrick
P
Schneider-Axmann
Thomas
T
Kemmer
Claudia
C
Usher
Juliana
J
Reith
Wolfgang
W
Meyer
Jobst
J
Falkai
Peter
P
D000328:Adult; D000367:Age Factors; D000483:Alleles; D000679:Amygdala / Q000473:pathology*; D001714:Bipolar Disorder / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology*; D016022:Case-Control Studies; D005260:Female; D007839:Functional Laterality; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D011569:Psychiatric Status Rating Scales; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D012737:Sex Factors
D050486:Serotonin Plasma Membrane Transport Proteins