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Rapid In Situ Hybridization using Oligonucleotide Probes on Paraformaldehyde-prefixed Brain of Rats with Serotonin Syndrome
Published on: September 23, 2015
Seasonal affective disorder and serotonin-related polymorphisms
C Johansson1, C Smedh, T Partonen
1Neurogenetics Unit, Karolinska Institutet and Karolinska Hospital, Stockholm, S-171 76, Sweden. carolina.johansson@cmm.ki.se
Neurobiology of Disease
|April 13, 2001
Summary
Genetic variations in serotonin transporter genes do not appear to be a major cause of seasonal affective disorder (SAD) in Northern Europe. This study found no significant associations in a European population sample.
Area of Science:
- Neuroscience
- Genetics
- Psychiatry
Background:
- Central serotonergic systems are implicated in seasonal affective disorder (SAD).
- Previous studies suggested a link between the serotonin transporter promoter repeat length polymorphism (5-HTTLPR) and SAD in American populations.
Purpose of the Study:
- To investigate the association between specific serotonin gene polymorphisms and SAD in a Northern European population.
- To examine the role of these genetic variations in seasonality.
Main Methods:
- Genotyping of 82 SAD patients and 82 healthy controls from Sweden, Finland, and Germany.
- Analysis of the serotonin transporter promoter repeat length polymorphism (5-HTTLPR) and five other polymorphisms in serotonin receptor genes (5-HT2A, 5-HT2C), tryptophan hydroxylase, and white matter genes.
Main Results:
- No significant associations were detected between the studied polymorphisms and SAD.
- No significant associations were found between these polymorphisms and seasonality.
Conclusions:
- The investigated serotonin gene polymorphisms do not appear to play a major role in the pathogenesis of SAD in the Northern European population.
- While minor effects cannot be entirely ruled out, these genetic factors are unlikely to be primary drivers of SAD in this demographic.
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